>Regional forms
We already know these we've had them since Alola, apparently only Wooper and Tauros get one this generation.
>New evolutions
We know about these too, cross gens are back we haven't had this many for a while, regular pokémons that we know get a new evolution.
>Ancient species
Some pokemon who apparently aren't from our time but from the past who came in our timeline they are ancestors of pokemon we know of already. They apparently can't evolve.
>Future species
Some pokemon who apparently aren't from our time but from the future who came in our timeline they are descendants of pokemon we know of already. They apparently can't evolve.
>Convergent species (RFakes)
They are completely different species of pokemon with a new name and new dex number but they look like pokemon we know of already, this phenomenon can be explained because they've evolved through years and came at the same conclusion that this body was the best one they could have to survive in the wildlife. We know of Diglett having a convergent species which is an eel instead of a mole.
>New group of pokemon
We don't know anything about them except that they are akin to UB in strength and as a group that differentiates itself from normal pokemon.
