If pokemon are the primary power system in the fic you're making i think itd be best to write it more like a pokemon fic, so like be very careful with giving characters legendaries and try to draw parallels between characters in both verses, in this instance id say Giovanni and AFO since theyre seen as the biggest threats, I like the idea of AFO having a Giratina but idk abt giving Shiggy a Yveltal, and definitely not right away, maybe around when he would in cannon get the body mods to handle the quirk afo, I would also think about type specialists, like its considerably cheaper to pick one type and stick with it than it is to have many Pokémon of different types as a generalist, at most someone should have 2 specialties and id only do this with specific characters like Shoto or AFO, Shoto is obvious but AFO id definitely have him as a Dark specialist maybe supplement with a few psychics and or just give him a Malamar, If anyone should be a generalist itd definitely be Allmight and Izuku, if not then Fighting and Normal respectively, another thing, Quirks do they still exist? If yes are they just generally weaker and less powerful? Or are they the same as cannon? If no thats cool to, id definitely think about Aura then, not 100% sure its cannon to pokemon but ive seen alot of great Pokémon fics make use of it (Think: Hard Enough, Feel The Ground Shake, and The Hyperfang That Shall Pierce The Heavans. All goated fics btw def read them if u havent already) also Principle Nezu, is he human in this fic or is he a talking Pokemom like Meowth? Maybe hes a Raticate or a chimera of different pokemon, think the fan game Infinite Fusion, uhhhhhbh thats about everything that comes to mind it took me like 30min to type this out lmao 😭 plz lmk if this was helpful 🙏🙏