I'm pretty sure this list was made before but since it seems like some people here keep mentioning pokemon that have already been confirmed to be in the game here is a list of pokemon already confirmed to be in the game by type(let me know if I'm missing any, also I will try to keep this list updated.):
Grass:Grookey,Eldegoss,Leafeon,Tsareena,Abomasnow,Roserade,Ludicolo
Fire:Scorbunny,Flareon,Arcanine,Charizard,(Kanto)Ninetales
Water:Sobble,Drednaw,Wishiwashi,Wailord,Vaporeon,Jellicent,Seismitoad,Mantine,Milotic,Pelipper,Lanturn,Gyarados,Seaking,Quagsire,Ludicolo,Golisopod
Electric:Yamper,Raichu,Vikavolt,Jolteon,Lanturn,Galvantula,Manectric
Flying:Corviknight,Noctowl,Braviary,Butterfree,Charizard,Hawlucha,Mantine,Pelipper,Gyarados,Vespiquen,Drifblim,Togekiss,Noivern
Rock: Drednaw,Tyranitar,Rhyperior,Onix,Gigalith
Ground:Flygon,Pupitar,Hippowdon,Rhyperior,Steelix,Golurk,Mudsdale,Seismitoad,Diggersby,Quagsire,Dugtrio
Steel:Corviknight,Lucario,Steelix,Bronzong
Psychic:Meowstic,Espeon,Wobbuffet,Malamar,Bronzong,Gardevoir and Gallade,Mew
Ghost: Dusknoir,Golurk,Gengar,Jellicent,Mimikyu,Drifblim,Froslass
Dark:Impidimp,Hydreigon,Tyranitar,Umbreon,Pangoro,Malamar,Weavile
Fairy:Impidimp,Sylveon,Slurpuff,Gardevoir,Clefable,Togekiss,Mimikyu
Dragon:Hydregion,Haxorus,Goodra,Noivern
Ice:Glaceon,Abomasnow,Avalugg,Vanilluxe,Glalie and Froslass,Weavile
Poison:Gengar,Roserade,Garbodor
Bug:Vikavolt,Butterfree,Vespiquen,Galvantula
Fighting:Lucario,Sawk,Bewear,Hawlucha,Pangoro,Machamp,Gallade
Normal:Wooloo,Cinccino,Noctowl,Braviary,Snorlax,Eevee,Bewear,Diggersby
Pokemon that we don't currently know the types for:Zacian,Zamazenta