Okay, so I have a bakudeku au idea where a quirkless Izuku eventually ends up becoming Pro Hero Dynamight's Louis Lane of sorts. In this au, Izuku never gets the OFA quirk and doesn't get into UA. He and Katsuki don't keep in touch, etc. However, Izuku is still a hero/quirk nerd at heart, and despite everything, he still cares about Katsuki, so he starts an anonymous blog. Rather than focusing solely on pro heroes, it focuses on quirks in general, and while he does make posts about the quirks of pro heroes, he is especially interested the quirks of the up and coming new generation of heroes at UA and how they develop.
It starts with an in-depth analysis of the sports festival, and even though he doesn't mean for it to be the case, it is fairly obvious that the focus of the analysis almost always shifts to Katsuki. The blog picks up attention after that, and people are interested in the analyses as well as who is making them since the only clue is the fact that each post is signed off with the initials DK. Katsuki, of course, doesn't pay any attention to the blog, but his classmates are worried that a stranger on the internet is analyzing the strengths and weaknesses of their quirks for any villain to read and take advantage of.
Aizawa isn't too worried about it and uses it as a teaching moment. If some rando on the internet can figure out their weak points by observing them from afar, any opponent who faces them could do the exact same. Instead of being worried about their weaknesses being revealed, they could use the analyses to figure out what they need to work on so that they no longer have that weakness. Essentially, according to Aizawa, the anonymous DK blog is doing a large part of their work for them, and they should be grateful.
Katsuki, once again, thinks anyone who relies on someone else to do their work for them isn't worthy of being a hero and adamantly refuses to check out the blog, even when the bakusquad mentions his prominence on it.
This all changes when Katsuki is kidnapped. Izuku finds out pretty quickly when his mom visits the Bakugos that Kasuki has been kidnapped by villains and taken somewhere unknown. Logically, he knows he should leave it to the pro heroes, that there's not much a quirkless kid like him could do, but he's always had self-sacrificing tendencies, and that's still his Kacchan in danger, so he goes sleuthing. He tells himself he's just practicing his investigative journalism.
He does research on the villains who have attacked UA recently, any video evidence of the quirks used, digital footprints of similar quirks being used, etc. In running his blog, he's gotten a bit tech savvy and maybe gets into things he probably shouldn't have access to. He's able to narrow down a potential hideout location and basically stalks the area, maybe even skips school or sneaks out at night to do so, until he spots one of the league members and follows them from afar to what looks like a back alley bar entrance. He really has no way of knowing if this is the actual hideout or if Katsuki is actually in there, but if he risks going inside and gets captured, then the location would be trapped along with him. At the very least, the heroes can maybe capture a member of the league from there and get the actual location.
He anonymously drops a pin of the location with an explosion emoji (💥) to pro heroes. Apparently, they're so busy trying to figure out who sent it to actually act on the info, so he sends it to UA teachers who once again are told to wait until the pro heroes investigate. Getting desperate, Izuku sends the pin with the emoji to the class of 1A who actually do act on it, and Katsuki escapes/is rescued similarly to canon.
Having done some good and learning that Kasuki's class and the students of UA are being targeted by the league, Izuku decides to use the DK blog and his investigative journalism to help, but he knows that he has to keep it all anonymous or the heroes will probably shut him down. He continues his blog as usual, but as the plot progresses, he secretly sleuths to find information for the heroes and class 1A to help them get to places faster. He analyzes the quirks of villains, including potential strategies of taking them down, and anonymously sends the analyses to the heroes and students to help prep them for upcoming battles. He never posts those particular analyses to his blog until after the villain is apprehended, and he never posts about the restricted information he sends to the heroes.
He also sets up an ask box where people can submit videos of quirks in use or the names of particular heroes/villains to get his analysis on them. If it's a casual ask, he'll post the analysis to his blog, but really, the function is meant to set up a line of communication where heroes and UA students can get his input by directly asking him. For these, he is pretty good at figuring out who is sending the ask, even if it's anonymous, and sends his response directly to the person asking, which also raises concerns about the security of tech at UA and pro hero agencies.
He does all of this for free because setting up any sort of monetary transaction would really be the only way anyone could track him down with the safe guards he's put in place.
He also reports on battles between heroes/UA students and villains that aren't strictly classified to the public, and his blog becomes THE go-to source for such news. Professional news sources are envious. The heroes are divided on whether he is a menace or a boon to society. There are some who claim that what DK is doing counts as vigilante work and is illegal. His supposed hacking of professional organizations definitely is. There's also speculation on what DK's quirk must be for him to do what he does. Oh, if only they knew.
Through all of this, Katsuki remains stubborn about not looking at the blog or using any info from this hack. If he can't beat these villains and become the number one pro hero on his own, then it won't be worth anything. His friends constantly pester him to check the blog out because it's pretty clear to them that whoever DK is, they are particularly fascinated with Katsuki. Katsuki thinks this is only natural since he is obviously the best, and everyone else are just extras.
The plot obviously shifts based on the intell from DK, so who knows who ends up living instead of dying in this version, which secrets get revealed sooner, etc. Dealer's choice.
Things go back to normal in class 1A's second year, and the DK blog continues to run as usual, but there's less constant pressure with AFO and the league dealt with. It isn't until their third and final year that something unexpected happens, and the identity of DK is finally exposed to the public. It turns out that instead of some super badass vigilante adult with a complex quirk, DK is nothing more than a high school student with a special interest. A QUIRKLESS high school student with a special interest, no less. The public is flabbergasted and honestly impressed. Bigots refuse to believe it.
Kasuki is kind of enraged. He finally decides to check out the blog that is apparently run by Deku (uggghhh! There's no way he seriously used DK as a reference to his childhood nickname/insult!). He starts from the beginning, and it's obvious to him almost immediately that, yup, this DK is definitely Deku. This blog has the same format and writing style, if not a bit more formal, as the old hero/quirk journals the nerd used to keep. He's almost more mad at himself because had he not been so stubborn, he could have solved this years long mystery on day one. He's almost obsessed with going through the entire blog and the analyses, and the extras (his friends) were right. He features pretty prominently throughout the blog.
Was this whole thing a way to get his attention? To spite him? How often did Deku put himself in danger just to write a post for this stupid blog or to tip off the heroes and his class? Jokes on him because Katsuki never fucking cared. He still doesn't care.
He's definitely not relieved when Deku isn't charged with being a vigilante when he argues he was practicing his journalism skills, which he plans to study after high school. The DK blog was a fan blog that didn't post anything that wasn't analyzing public or willingly submitted footage or something he just so happened to witness with his own eyes as a bystander. He also points out/claims that he never hacked any private systems. All of his communications were made using information found on social media or public data resources, and last time he checked, using a VPN wasn't illegal. (He definitely did hack into shit he wasn't allowed in, but he didn't leave any evidence that they could use to actually prove anything.) He never personally confronted any villains, and he doesn't even have a quirk, so even if he had, the vigilante rule wouldn't apply to him anyways because it only specifies the unauthorized use of one's quirk.
Like he said, Katuki doesn't give a fuck, but that doesn't stop him from banging on Deku's door to confront the nerd about it all. Izuku, for once, is embarrassed and admits he started the blog as a way to stay connected to his childhood friend and track his progress as he made his way to be the number one pro hero. He used it as a space to voice his hobby. He didn't expect the DK blog to gain traction the way it did, and he never planned to essentially spy for the heroes during the war with the League and AFO, but he couldn't bring himself to stand by and do nothing when he learned Kacchan was in danger.
Katsuki angrily claims that he doesn't and never needed Deku's help and that he never looked at his blog until recently and that he better be glad for that fact because it was so obviously him that he would have been caught way before now had Katsuki ever lowered himself to read it.
Izuku admits that he knows Kacchan never needed his help, but he selfishly wanted to keep him in his life in some way anyway. Katsuki doesn't know what to say to that and is glad when Izuku continues by saying that helping heroes was the next best thing to being a hero in his mind.
When Katsuki asks what his plan is now that his blog is shut down, Izuku cheerfully says that nothing on his blog was actually illegal, so they can't really shut it down, only monitor it and his own digital footprint more closely for any illegal activity. Izuku was originally planning to go to university to study journalism, but since his identity was revealed, he probably won't need to do that after all. Now that he doesn't have to worry about staying anonymous, he can finally set up a way for people to submit commissions to his blog for him to do analyses of specific quirks. He's also already been asked to do consultation work for a handful of pro hero agencies and hero schools, including UA. Additionally, several pro hero centered newspapers and magazines have solicited him to hire him after he graduates high school. He plans to accept one of their offers and continue to run his DK blog (which he will officially rebrand as the Deku blog now that the cat is out of the bag) and quirk consultation hustle on the side.
"Isn't it exciting, Kacchan? You're going to be the number one pro hero, and I'm going to be the number one pro hero journalist and quirk analyst! Well, that is if you can manage to improve [insert weakness here] that I noticed during the past two sports festivals ;)"
Katsuki is almost too distracted to be mad about that last comment since he's being bombarded with visions of a future where his nerd is constantly throwing himself into danger to get his story, and it will be up to Kasuki to make sure his nerd doesn't fucking die. Fuck.
And all of that brings us to the Lois Lane of it all because professional pro hero journalist Deku is constantly the first to arrive at any hero/villain confrontation and uses his investigative journalist skills to get the latest scoop on the under world of the city, and it is up to the number one pro hero Dynamight to save his ass every single time. Dynamight acts pissed about it, but if any other hero saves his Deku before he can, he gets even more pissy.
Villains who want to get to Dynamight try to target Izuku, but for being quirkless the man is still pretty capable of taking care of himself, and it also becomes clear that targeting Izuku is a garunteed brutal ass beating/death sentence at the hands of Dynamight for anyone involved, so that strategy is relatively short lived.
Dynamight and Deku become the biggest "will they won't they" amongst Dynamight's fans, and it does take a long time for them to figure their shit out, but they do get there and eventually start dating.
