@2002PokeFan9605
Here's my updated habitat list. I'd like to note that everything listed here is my own subjective opinion, which is based upon a few factors: the creature the Pokémon is based upon, where similar Pokémon are placed, and/or my own interpretations of the limited categories give. I don't like the categorization considering it's very limited, there's no options for a desert, river, or snowy area, for example, and "water's-edge" and "rough-terrain" are pretty vague and subjective terms.
Spoiler

Grassland	Forest	Water's-edge	Sea	Cave	Mountain	Rough-terrain	Urban	Rare
Rattata (Alola)	Exeggutor (Alola)	Slowpoke (Galar)	Corsola (Galar)	Diglett (Alola)	Sandshrew (Alola)	Marowak (Alola)	Meowth (Alola)	Articuno (Galar)
Raticate (Alola)	Ponyta (Galar)	Slowbro (Galar)	Shellos	Dugtrio (Alola)	Sandslash (Alola)	Burmy (Sand)	Meowth (Galar)	Zapdos (Galar)
Farfetch'd (Galar)	Rapidash (Galar)	Slowking (Galar)	Gastrodon	Bronzor	Vulpix (Alola)	Wormadam (Sand)	Persian (Alola)	Moltres (Galar)
Zigzagoon (Galar)	Turtwig	Pipulp	Finneon	Bronzong	Ninetails (Alola)	Bonsly	Grimer (Alola)	Uxie
Linoone (Galar)	Grotle	Prinplup	Lumineon	Spiritomb	Geodude (Alola)	Hippopotas	Muk (Alola)	Mesprit
Shinx	Torterra	Empoleon	Mantyke	Gible	Graveler (Alola)	Hippowdon	Mr. Mime (Galar)	Azelf
Luxio	Chimchar	Bidoof	Phione	Gabite	Golem (Alola)	Skorupi	Burmy (Trash)	Dialga
Luxray	Monferno	Bibarel	Manaphy	Garchomp	Munchlax	Drapion	Wormadam (Trash)	Palkia
Cranidos	Infernape	Buizel	Tirtouga	Mismagius	Riolu	Magnezone	Drifloon	Giratina
Rampardos	Starly	Floatzel	Carracosta	Probopass	Lucario	Rhyperior	Drifblim	Cresselia
Shieldon	Staravia	Croagunk	Frillish	Froslass	Magmortar	Tepig	Glameow	Darkrai
Bastiodon	Staraptor	Toxicroak	Jellicent	Heatran	Gliscor	Pignite	Purugly	Arceus
Buneary	Kricketot	Carnivine	Alomomola	Regigigas	Minccino	Emboar	Mime Jr.	Victini
Lopunny	Kricketune	Oshawott	Tynamo	Roggenrola	Cincinno	Sandile	Happiny	Cobalion
Chingling	Budew	Dewott	Eelektrik	Boldore	Cubchoo	Krokorok	Leafeon	Terrakion
Lickylicky	Roserade	Samurott	Eelektross	Gigalith	Beartic	Krookodile	Glaceon	Virizion
Tangrowth	Burmy (Plant)	Tympole	Vivillion (Marine)	Woobat	Mienfoo	Darumaka	Porygon-Z	Tornadus
Electivire	Wormadam (Plant)	Palpitoad	Vivillion (Archipelago)	Swoobat	Mienshao	Darumaka (Galar)	Gallade	Thundurus
Mamoswine	Mothim	Seismitoad	Vivillion (Ocean)	Drilbur	Pawniard	Darmanitan	Rotom	Reshiram
Shaymin	Combee	Basculin	Inkay	Excadrill	Bisharp	Darmanitan (Galar)	Lillipup	Zekrom
Snivy	Vespiquen	Ducklett	Malamar	Yamask	Vivillon (High Plains)	Maractus	Herdier	Landorus
Servine	Pachirisu	Swanna	Binacle	Yamask (Galar)	Bergmite	Dwebble	Stoutland	Kyurem
Serperior	Cherubi	Stunfisk	Barbaracle	Cofagrigus	Avalugg	Crustle	Pidove	Keldeo
Patrat	Cherrim	Stunfisk (Galar)	Skrelp	Joltik	Volcanion	Scraggy	Tranquill	Meloetta
Watchog	Ambipom	Rufflet	Dragalge	Galvantula	Jangmo-o	Scrafty	Unfezant	Genesect
Purrlion	Honchkrow	Braviary	Clauncher	Ferroseed	Hakamo-o	Sigilyph	Audino	Xerneas
Liepard	Stunky	Froakie	Clawitzer	Ferrothorn	Kommo-o	Vivillion (Polar)	Timburr	Yveltal
Blitzle	Skuntank	Frogadier	Popplio	Axew	Minior	Vivillion (Tundra)	Gurdurr	Hoopa
Zebstrika	Chatot	Greninja	Brionne	Fraxure	Duraludon	Vivillion (Icy Snow)	Conkeldurr	Type: Null
Munna	Snover	Vivillion (River)	Primarina	Haxorus	Kubfu	Vivillion (Sandstorm)	Throh	Silvally
Musharna	Abomasnow	Vivillion (Monsoon)	Wishiwashi	Druddigon	Urshifu	Honedge	Sawk	Tapu Koko
Cottonee	Weavile	Goomy	Mareanie	Golett	Doublade	Trubbish	Tapu Lele
Whimsicott	Togekiss	Sliggoo	Toxapex	Golurk	Aegislash	Garbodor	Tapu Bulu
Bouffalant	Yanmega	Goodra	Bruxish	Deino	Helioptile	Gothita	Tapu Fini
Heatmor	Dusknoir	Crabrawler	Dhelmise	Zweilous	Heliolisk	Gothorita	Cosmog
Durant	Pansage	Dewpider	Nihilego	Hydreigon	Amaura	Gothitelle	Cosmoem
Bunnelby	Simisage	Araquanid	Cramorant	Larvesta	Aurorus	Solosis	Solgaleo
Diggersby	Pansear	Wimpod	Arrokuda	Volcarona	Hawlucha	Duosion	Lunala
Vivillion (Meadow)	Simisear	Golisopod	Barraskewda	Carbink	Rockruff	Reuniclus	Necrozema
Vivillion (Savanna)	Panpour	Sandygast	Clobbopus	Noibat	Lycanroc	Vanillite	Magearna
Vivillion (Sun)	Simipour	Palossand	Grapploct	Noivern	Mudbray	Vanillish	Marshadow
Litleo	Sewaddle	Pyukumuku	Cursola	Diancie	Mudsdale	Vanilluxe	Guzzlord
Pyroar	Swadloon	Sobble	Zygarde	Salandit	Klink	Poipole
Skiddo	Leavanny	Drizzile	Drampa	Salazzle	Klang	Naganadel
Gogoat	Venipede	Inteleon	Rolycoly	Turtonator	Klinklang	Stakataka
Tyrunt	Whirlipede	Chewtle	Carkol	Pheromosa	Elgyem	Blacephalon
Tyrantrum	Scolipede	Drednaw	Coalossal	Silicobra	Beheeyem	Zeraora
Yungoos	Petilil	Toxel	Runerigus	Sandaconda	Litwick	Dracozolt
Gumshoos	Lilligant	Toxtricity	Dreepy	Falinks	Lampent	Arctozolt
Grubbin	Archen	Eiscue	Drakloak	Chandelure	Dracovish
Charjabug	Archeops	Pincurchin	Dragapult	Vivillion (Garden)	Arctovish
Vikavolt	Zorua	Regieleki	Vivillion (Elegant)	Zacian
Oricorio (Balie)	Zoroark	Regidrago	Vivillion (Modern)	Zamazenta
Oricorio (Pom-pom)	Deerling	Vivillion (Fancy)	Eternatus
Cutiefly	Sawsbuck	Vivillion (Pokéball)	Glastrier
Rimbombee	Emolga	Furfrou	Spectrier
Scorbunny	Karrablast	Espurr	Calyrex
Raboot	Escavalier	Meowstic
Cinderace	Foongus	Spritzee
Gossifleur	Amoonguss	Aromatisse
Eldegoss	Shelmet	Swirlix
Wooloo	Accelgor	Slurpuff
Dubwool	Chespin	Sylveon
Obstagoon	Quilladin	Klefki
Sirfetch'd	Chesnaught	Mimikyu
Stonjourner	Fennekin	Yamper
Cufant	Braixen	Boltund
Copperajah	Delphox	Sinistea
Fletchling	Polteageist
Fletchinder	Perrserker
Talonflame	Mr. Rime
Scatterbug	Milcery
Spewpa	Alcremie
Vivillion (Continental)	Indeedee
Vivillion (Jungle)
Flabébé
Floette
Florges
Pancham
Pangoro
Dedenne
Phantump
Trevenant
Pumpkaboo
Gourgeist
Rowlet
Dartrix
Decidueye
Litten
Torracat
Incineroar
Pikipek
Trumbeak
Toucannon
Oricorio (P'au)
Oricorio (Sensu)
Fomantis
Lurantis
Morelull
Shiinotic
Stufful
Bewear
Bounsweet
Steenee
Tsareena
Comfey
Organuru
Passimian
Komala
Togedemaru
Buzzwole
Xurkitree
Celesteela
Kartana
Grookey
Thwackey
Rillaboom
Skwovet
Greedant
Rookidee
Corvisquire
Corviknight
Blipbug
Dottler
Orbeetle
Nickit
Thievul
Applin
Flapple
Appletun
Sizzlipede
Centiskorch
Hatenna
Hattrem
Hatterene
Impidimp
Morgrem
Grimmsnarl
Snom
Frosmoth
Morpeko
Zarude