2P AU: Harmony's Personality & Motivations
Harmony is a "two sides" sort of character.
While she may not be as good at battling as Paxton or Taunie/Urbain, she's still competent. In Team MZ's she's after those two and equal to Lida. She has the talent, just not the competitive drive.
However, that doesn't mean she lacks drive altogether. Harmony's smart in a "calculating smart" sort of way. Paxton's strategic in that he can find a way to win a battle, but Harmony plays the long game. She wants to make sure her Pokémon, her friends, and she herself are set for a safe and comfortable life. She doesn't want others to worry or be hurt; hence her own aversion to battling for competition's sake after having to watch Paxton go through so much stress competing in the Galar Championship.
Except Harmony doesn't act smart. All of her experience working with and caring for people and Pokémon alike have taught her that her service is best appreciated when she's harmlessly nice and adorable. She's silly and a little bit stupid at times, in a loveably naive way. After all, who could blame her for her mistakes when she was so innocent and wholesome? Harmony's careful to maintain that she is impossible to hate. She's developed a sort of customer service persona, and it's carelessly easy for her to embrace.
Don't get this wrong, Harmony can be smart, and she will be direct when it matters. She contributes her share in Team MZ's strategy meetings, makes sure their "missions" are being completed, and keeps a steady stash of healing items for whenever they're needed. But when she doesn't have to, she'll take it easy and provide support to those taking the brunt of the stress.
Hence why she doesn't take competition as seriously. It also helps that playing herself off as a less battle-intense trainer makes her less threatening and more welcoming. She has a balance to maintain in being the powerful hero who guided Zygarde in saving Lumiose, while remaining a relatable, trustworthy "girl next door" who could helpfully watch over your Pokémon and ensure they're well taken care of.
Harmony believes in spreading positivity, joy, and whimsy. As a result, she keeps snarky or mean comments to herself. if something mildly annoys her, she might act dramatically mopey to be funny, but she rarely shows serious sadness. If she's more severely upset by something, she'll go find somewhere to be alone and let it out "harmlessly", typically punching pillows in her room or rambling to her Pokémon until she feels better. She knows that conceptually, holding back anger only makes problems worse, yet in practice, she still feels a need to not burden others with her negative thoughts.
Part of her refusal to show negativity is in loving all Pokémon equally. She can and will treat anything and everything as cute. From the normally cute stuff like Fennekin and Eevee to the Alpha Whirlipede that is probably trying to kill her. She has two motivations for this behaviour. One, it encourages more customers by telling them that no matter how weird their Pokémon are, she won't care. She'll love them even if they're typically scary or dangerous. Two, it lets her have whoever she wants on her team while playing it off as a wholesome naivety.
Harmony's lovable, but she's intentionally lovable with the goal of befriending everyone for mutual safety. If she could convince everyone to be nice to each other and not fight for her sake, the world would be better, right?
Harmony's quirky, kind, yet unassuming presentation over a calculating, careful true self is represented by the original gimmick I'm giving her: Revitalizing Tea. She brews Revitalizing Twigs (like the ones from the Fennekin sidequest) into tea by... cooking them in a kettle with water. It creates a strongly bitter tea that is a powerful invigorant and antidote, as well as seemingly amplifying Harmony's friendship benefits with her team, possibly a side effect due to how she consistently gives it to them over a long time. Pokémon absolutely love it, as well as Harmony's cooking in general. It may be addictive... but no one knows better! It's literally all a consequence of Harmony being a weirdo who cooks "sweet smelling" twigs in water... and also Harmony seemingly has a monopoly on it. Speculators are convinced she has some secret recipe to keep customers coming back for more, but the real secret is the fact that it's something so random yet simple that no one else tries it.
Harmony is Zygarde's chosen. She doesn't want to be Zygarde's chosen. Paxton wants to be a hero to save the city, why can't he deal with this stuff and leave her to run her daycare and befriend people? Unfortunately, her not wanting to be Zygarde's chosen doesn't change anything. So, cryptic chats with L, random battles with the Green Creature, and an annoying obstacle course through the city mid-apocalypse to meet up with the Green Creature to save the city it is. Thankfully, she has Paxton, the rest of the cast, and the power of Revitalizing Tea boosted friendship to help her through it all.
Could she have locked in and dealt with this herself? Yes but she doesn't want to. She wants to run her daycare and befriend people. So she delegates as much of it as she can to Paxton or the other MZ members.
As a general note, Harmony has been assigned various alternate promotion match opponents since I find it a bit unrealistic to have both Paxton and Harmony face the same person for each promotion. Harmony does fight Zach after Paxton because he's the Eternal Z, but the others are different. I haven't really bothered to pick Y or X opponents for her, and then she gets the jump from V to F after fighting Vinnie like Paxton and Taunie. Afterwards, F Rank promotion match is against Gwynn, with Harmony being "behind" enough that she's searching for Gwynn for her own promotion match at the same time Paxton is searching for her to have his promotion match with Ivor. Harmony's E Rank promotion match opponent is a random Ace Trainer. Her D Rank promotion match opponent is Corbeau, the only promotion match from the game I chose to give to her so that she gets to be in someone's character arc instead of Paxton. Harmony's C Rank promotion match is against the battle tactics teacher at the Academy Étoile, forcing her to wait at the Academy all day for her opponent to have a break to battle her while Paxton does Jacinthe's tournament. Her B Rank promotion match opponent is Griselle, so she accompanies Paxton through the Team Flare Nouveau arc.
After the events of the ZA maingame plot, Harmony continues to run her daycare based in Hotel Z. Sure, the location wasn't exactly what she's intended, but she's doing what she came here for, and finally, all seems well.
She likes to visit the Rust Syndicate to inflict her brand of whimsy upon them now that she has proven to the grunts that she can beat them up if they don’t let her into their Cool Building. (Harmony saw that there was a unique building on like day 2 or 3 in Lumiose, went “i bet there’s something interesting in there”, tries to barge in, gets thrown out by the guards in 2 seconds, and decides she will make sure to be back one day when she has a proper team.) She introduces them to Revitalizing Tea and also just a general sunshine for them, so the grunts quickly bond with her and appreciate her presence. Philippe also loves her in a “how are you so wholesome, dear child (Corbeau is so traumatized, probably so are most of the grunts)”. Corbeau tolerates her at first since while nice, she’s technically being disruptive. He’s also very suspicious of why she’s way nicer to them than the rest of Team MZ despite the whole loan sharking Taunie/Urbain fiasco. This leads to Corbeau eventually being the “first” to “figure out” that Harmony is pretending very hard to be nice and harmless (in that Harmony had simply told Team MZ that she feels pressured to be super upbeat and innocent, instead of waiting for them to question about it). He appreciates her more for actually having thoughts and having carefully planned out a way to make things work the way she wants them after that. Oh, and Harmony’s whole goal in befriending the Rust Syndicate? It gives her an emergency safety net of trainers who would defend her establishment in case Paxton and the other MZ members aren’t able to make it. She could technically step up and do the defending herself, but she wants to make it clear that her team is nice and harmless even if some of them look scary, so they must fight as little as possible. “Don’t mess with Harmony, she’s so kindhearted everyone wants to protect her, including the local mafia.”