A new trailer has been released detailing several new Pokémon that will be available in Sun/Moon.
Silvally evolves from Type-Null, is Normal-type, and has the ability RKS System, which causes its type to change based on the item it's holding. This functions similarly to Arceus with Multitype. Also like Arceus, it has a unique move that changes type based on that item, Multi-Attack.
Jangmo-o evolves into
Hakamo-o, which further evolves into
Kommo-o. Both are Dragon-/Fighting-type with Bulletproof or Soundproof. Kommo-o has the unique move Clanging Scales.
Steenee evolves from Bounsweet, is Grass-type, and has the abilities Leaf Guard or Oblivious. It further evolves into
Tsareena, also Grass-type, but instead with the abilities Leaf Guard or Queenly Majesty and a unique move called Trop Kick.
Ribombee evolves from Cutiefly, is Bug-/Fairy-type, and has the abilities Honey Gather or Shield Dust.
Grimer and Muk have both acquired Alola forms, both being Poison-/Dark-type and having the abilities Poison Touch and Gluttony.
In addition, the trailer reveals two new trainers: Olivia is the Kahuna of Akala Island, and Ilima is a Normal-type specialist Trial Captain,
Source:
Official site: More Pokémon of Alola