Do I need to catch all Pokémon once or complete the dex to fight Arceus?

Question

Like is it enough to have caught them or do I need to get 10 research points on all of the Pokémon?

Answer 1

You just need to catch all Pokémon.

Source: I have done this. (My last mon was Porygon-Z. I evolved my Porygon2, talked to Laventon, and he mentioned about the completed Dex.)