>>58222333>The "there are only 151 Pokemon known in the world" you speak of is from the Gameboy timeline.It's from the OG treatment of Pokémon, where they lived in the real world, alongside humans and real animals and adhered to the original timeline regarding discovery of Pocket Monsters (there were only 151 identified, because humans only started studying them in the late 1800's, despite noticing they were a thing).
There's only one core timeline, even ORAS just proves a multiverse (The events of RG and GS occur alongside the events of RS and DP regardless of version of game you play; rest of the franchise still treats Kalos as the region where ME was discovered, despite ORAS claiming it was Hoenn, then mentioning a Hoenn where ME did not exist, which was the Hoenn presented in Gen 3 and which the events of XY happen years after the events of RSE). Same with USM, which tell a differing story to SM, with some similarities (indicating this was a universe where events happened differently, like Lusamine not having a complete mental break), or indeed the rest the rehashes where they re-tread the storyline of the canonical entries but with the third legendary being the focus catch
