Pokémon with a 4x Weakness to Flying Press:
Normal/Grass- Deerling, Sawsbuck
Normal/Ice
Normal/Fighting- Meloetta (Pirouette Form), Mega Lopunny, Stufful, Bewear
Normal/Dark- Alolan Rattata, Alolan Raticate
Grass/Ice- Snover, Abomasnow
Grass/Fighting- Breloom, Virizion, Chesnaught
Grass/Dark- Nuzleaf, Shiftry, Cacturne
Ice/Fighting- Crabominable
Ice/Dark- Sneasel, Weavile
Fighting/Dark- Scraggy, Scrafty, Pangoro
Pokémon with a 4x Weakness to Flying Press when hit with Forest's Curse:
Water/Normal- Bibarel
Fire/Normal- Litleo, Pyroar
Ground/Normal- Diggersby
Rock/Normal
Bug/Normal
Steel/Normal
Dragon/Normal- Drampa
Water/Ice- Dewgong, Cloyster, Lapras, Spheal, Sealeo, Walrein
Fire/Ice
Ground/Ice- Swinub, Piloswine, Mamoswine
Rock/Ice- Amaura, Aurorus
Bug/Ice
Steel/Ice- Alolan Sandshrew, Alolan Sandslash
Dragon/Ice- Kyurem
Water/Fighting- Poliwarth, Keldeo
Fire/Fighting- Combusken, Blaziken, Monferno, Infernape, Pignite, Emboar
Ground/Fighting
Rock/Fighting- Terrakion
Bug/Fighting- Heracross, Buzzwole, Pheromosa
Steel/Fighting- Lucario, Cobalion
Dragon/Fighting Hakamo-o, Kommo-o
Water/Dark- Carvanha, Sharpedo, Crawdaunt, Greninja, Mega Gyarados
Fire/Dark- Houndour, Houndoom, Incineroar
Ground/Dark- Sandile, Krokorok, Krookodile
Rock/Dark- Tyranitar
Bug/Dark
Steel/Dark- Pawniard, Bisharp
Dragon/Dark- Deino, Zweilous, Hydreigon, Guzzlord
Pokémon with a 1/4 Resistance to Flying Press:
Electric/Poison
Electric/Flying- Zapdos, Rotom Fan, Emolga, Thundurus, Oricorio (Pom-Pom Style)
Electric/Psychic- Alolan Raichu
Electric/Fairy- Dedenne, Tapu Koko
Poison/Flying- Zubat, Golbat, Crobat
Poison/Psychic
Poison/Fairy
Flying/Psychic- Zatu, Xatu, Lugia, Woobat, Swoobat, Sigilyph,Oricorio (Pa'u Style)
Flying/Fairy- Togetic, Togekiss
Psychic/Fairy- Mr. Mime, Ralts, Kirlia, Gardevoir, Mime Jr., Tapu Lele
There are no Pokémon that have a 1/4 Resistance to Flying Press when hit with Forest's Curse.
Hope I helped :)