KANTO

egg

Articuno
Mew
Mewtwo
Moltres
Tauros [aqua]
Tauros [combat]
Zapdos

pkm

Aerodactyl [mega]
Alakazam [mega]
Beedril [mega]
Blastoise [mega]
Charizard [mega, x+y]
Gengar [mega]
Gyarados [mega]
Kangaskhan [mega]
Kingdra
Magneton
Mewtwo [mega, x+y]
Muk
Pidgeot [mega]
Pinsir [mega]
Poliwrath
Rhyperior
Sandy Shocks (??? what the hell is that)
Scizor [normal + mega]
Scream Tail (????????)
Slowbro [mega]
Steelix [mega]
Sylveon
Venusaur [mega]
Victreebell

JOHTO

egg

Celebi
Entei
Ho-oh
Lugia
Raikou
Suicune
Unown [D,F,P,T,U,V,X]

pkm

Ampharos [mega]
Celebi
Flutter Mane (???????????????)
Great Tusk (????????????????????????????)
Heracross [mega]
Hitmontop
Ho-oh
Houndoom [mega]
Iron Bundle (okay i'm going to stop questioning these i guess. what?)
Iron Thorns
Iron Treads
Lugia
Magmar
Magmortar
Raging Bolt
Tyranitar [mega]
Walking Wake

HOENN

egg

Deoxys
Groudon
Jirachi
Kyogre
Latias
Latios
Rayquaza
Regice
Regirock

pkm

Aggron [mega]
Altaria [mega]
Banette [mega]
Blaziken [mega]
Camerupt [mega]
Castform [smow, rain, sun]
Claydol
Deoxys [attack, defense, speed]
Gallade [mega]
Gardevoir [mega]
Glalie [mega]
Gorebyss
Groudon [normal + primal(??)]
Huntail
Iron Hands
Iron Valiant
Kyogre [primal]
Latias [normal+mega]
Latios [mega]
Manectric [mega]
Mawile [mega]
Medicham [mega]
Metagross [mega]
Milotic
Rayquaza [normal+mega]
Regirock
Roaring Moon
Sableye [mega]
Salamence [mega]
Sceptile [mega]
Sharpedo [mega]
Swampert [mega]
Wailord

Sinnoh

egg

Arceus
Azelf
Cresselia
Darkrai
Enamorus
Finneon
Giratina
Heatran
Manaphy
Mesprit
Palkia
Regigigas
Shaymin
Uxie
Voltorb [hisuian]

pkm

Abomasnow [mega]
Arcanine [hisuian]
Arceus [+ all forms]
Avalugg [hisuian]
Basculegion
Braviary [hisuian]
Burmy [trash, sand]
Cherrim [sunny]
Decidueye [hisuian]
Dialga [origin]
Electrode [hisuian]
Enamorus [+ therian]
Garchomp [mega]
Gastrodon [occident]
Giratina [+origin]
Goodra [hisuian]
Heatran
Hippowdon
Kleavor
Liggigant [hisuian]
Lopunny [mega]
Lucario [mega]
Manaphy
Mesprit
Overqwil
Palkia [+origin]
Rotom [fan, freeze, mow]
Samurott [hisuian]
Shaymin [sky]
Sliggoo [hisuian]
Typhlosion [hisuian]
Ursaluna [+ blood moon]
Wormadam [trash]
Wyrdeer