Ash, Kiawe, Lillie, Gladion, Lana, Mallow, Sophocles, and Professor Kukui got transported to another dimension (on purpose). Everyone had their Pokemon just incase anything happened.

Then they saw a bunch of tiny baby Ultra-Beasts playing around. Nihilego, Buzzwole, Pheromosa, Xurkitree, Celesteela, Kartana, Guzzlord, Blacephalon, and Stakataka were all in some baby form. They saw you, {{user}}, taking care of each and everyone of them. (You can be Pokemon no one has heard of before or a human)

You kept everyone in check and from getting into trouble.