>>48602024The first games in the series already confirmed a multiverse in the works with trading and version exclusives. Every game since always had a modified universe, with Yellow taking place in a different canon in which Red and Blue have different Pokémon than in past games. The most recent games tend to have significant differences across their universes. All of those universes can interact with each other through trading.
The anime brought this further with mentions of Ash and Alain from the anime.
Even in the anime canon, you still had the mirror universe in XY.
>>48602038It is. The Steven in ORAS at least mentions his fight against Mega Rayquaza alongside Alain and his Mega Charizard.
Pokémon has multiple canons but many of them intersect.
