>>45156107Pokemon's usual ones especially since Gen III at least are;
> Early ForestViridian Forest, Ilex Forest, Petalburg Woods, Eterna Forest, Pinwheel Forest, Santalune Forest, N/A (Alola), Slumbering Weald
> Generic Rocky CaveMt. Moon, Dark Cave, Granite Cave, Oreburgh Gate/Mine, Wellspring Cave, Glittering Cave, Verdant Cavern, Galar Mine No.1/2
> Big MountainRock Tunnel, Mt. Silver, Meteor Falls, Mt. Coronet, Twist Mountain, (N/A) Kalos, Hokulani Observatory, N/A (Galar)
> GraveyardPokemon Tower, Burned Tower, Mt. Pyre, Lost Tower, Celestial Tower, Route 10 (Kalos), Hau'Oli Cemetery, N/A (Galar)
> Lake/Fisherman's RiverN/A (Kanto), Lake of Rage, Route 104 North, Lake Verity/Valor/Acuity, N/A (Unova), Route 16 (Kalos), Lake of the Moone/Sunne, Lake Miloch
> Sandy DesertN/A (Kanto), N/A (Johto), Route 111, Route 228, Desert Resort, Route 13 (Kalos, Debatably), Haina Desert, Potbottom Desert
> Volcanic ZoneN/A (Kanto), N/A (Johto), Mt. Chimney, Stark Mountain, Reversal Mountain, N/A (Kalos), Wela Volcano Park, N/A (Galar)
> Arctic ZoneSeafoam Islands, N/A (Johto), Shoal Cave, Route 216/217, Giant Chasm, Frost Cavern, Mount Lanakila, Route 10 (Galar)
Honestly it's less so that some of them are used, it's when they're used seemingly because the region needs to have that sort of location like Shoal Cave in Hoenn or Route 228 in Sinnoh or when it feels like you're just going from place of interest to place of interest without any downtime in-between like in Galar and Alola.