My vote is for All Media Types. The main series characters all appear in other media and usually have aspects of their other appearances incorporated into their characterizations.

I also nominated N & Mewtwo and if Pokémon is split, that would likely go into Crossovers which seems wrong when you can even transfer Mewtwo into N's games. Most people's Mewtwo characterizations come from the anime and from Detective Pikachu.

Pokémon Adventures/Special is a specific Pokémon canon, but the franchise is fundamentally multimedia and labelling as game-only or splitting based on games of primary appearances seems incorrect to me.