The two Pokemon they’re showing brief glimpses of in this trailer are, naturally, the two represented on each game box.
Solgaleo is from the cover of the Sun version and works as a Psychic and Steel type the brings a new move to the table called the Sunsteel Strike.
Lunala comes from the Moon version, respectfully. It’s a Psychic and Ghost type that comes with a defensive ability where it takes less damage from Pokemon with full HP. It’s also got a new attack shown off here called the Moongeist Beam.
There’s apparently a “new generation of Pokedexes” for players that starts with Rotom, a Pokemon introduced back in Diamond and Pearl, who can now speak to you.
The new area is composed of 4 major land masses and according the new character, Professor Kukui and his “mysterious assistant” Lillie, are all “chock full of nothin’ but rare Pokemon”.