A total of 357 Pokémon were available in Pokémon Pokopia at version 2.0.0.
The figure includes 300 Pokémon present at the game’s original release, 50 added with the Bubbly Basin DLC, and seven introduced through in-game events. Those three groups total 357.
The number is tied to version 2.0.0, so it should not be treated as a permanent total for every future update. Later downloadable content or events could change the roster.
Pokopia also uses its own Pokédex numbering system rather than simply reproducing National Pokédex numbers. That makes the game’s in-game list a distinct catalog, even though the Pokémon themselves come from across the wider Pokémon series.