I have the species swap au (humans<>cybertronians) of TFP which I'm still working on, but I also have a very vague Earthspark species swap au idea.
Instead of taking place during the tail end of World War III on a post-apocalyptic Earth, maybe the Earthspark edition would take place on Cybertron? Maybe humanity would be living there for some reason, and almost extinct? Not sure how exactly the backstory or the actual story would work.
Dot's name could still be "Dot" since it's also a word. She would transform into a pickup truck because she drives one, or a military vehicle since she's an ex-soldier. Maybe she was military colored and had a battlemask and/or visor during the war, but after the war stopped wearing them and changed her paint color to something else. She would have some kind of a peg leg with claws on the end, propably with a wheel attached so she can still drive.
Alex's name could be Alexandrite? I can't think of anything else that resembles "Alex". Idk what he'd transform into.
Mo's name could be Slo-Mo? Not sure, I don't know a lot of Cybertronian name-suitable words that sound like "Mo". Maybe she transforms into a small offroad motorcycle?
Idk Robby's cybertronian name, or what he'd transform into.
Idk Croft's name, some kind of a government vehicle like an armored car, spy van, or something. The kind of ones FBI and the like drive.
Idk Schloder's name, propably transforms into something similar to Croft but distinct from her. They shouldn't obviously be twins (though they are, because that's the only canonical way cybertronians have siblings). He wpuld have a visor.
Meridian's name would be "(Something) Atlas" to keep the map reference and because some cybertronian names are rendered in latin. He would transform into a spider because of the arachnamechs, but idk how to avoid him looking too much like Tarantulas. Also if I make him mainly white and green-eyed, he might end up looking like that Fox Kids repaint of BW Tarantulas. The spider's abdonmen could split in bot mode and be positioned in a way that invokes a labcoat, but idk beyond that. Still has the arachnamechs.
The terrans' human names are hard. I know at least americans give their kids weird names, but still. Terratronus' first name would be Terra though. Maybe I could get away with Jawbreaker only ever being called J.B.? The others are more difficult though.
They might not all be biologically related, since having five kids is pretty unusual in modern society.
The terrans should still be somehow unusual or have an abnormal origin in order for their importance to make sense. Maybe the remaining humans are too few to survive for more than a few generations, and the terrans were created from scratch in a lab?? Not sure how the plot would work then, especially if the twins and the triplets were still born separately, and Spitfire and Aftermath also separately or as a duo. How wpuld that work if Quintus was gone the while time and the humans were, idk, looking for him??
The other bots' human names are taken from my TFP species swap au and the humanformers G1 SG draft I wrote a while ago, the priority was to sound as much like the bot's real name as possible. I don't have surnames for most of them though;
Optimus Prime is Ryan Pax (idk the "Optimus Prime" part)
Shockwave is Shokufeh ???
Soundwave is Sündeviin ???
Nova Storm was named Novak Sturm in the G1 one and Skywarp was Skye Warper (not sure about the surname), but they're canonically sisters in Earthspark so having different surnames is kind of weird
Swindle is ??? Schwindler
There would propably be a few other humans in the background who might or might not get named.