Bulbasaur is the Pokémon whose Leafage helps create greenery in Pokémon Pokopia.
Pokopia lets the player’s human-shaped Ditto learn moves from other Pokémon and use those moves as practical tools while restoring the world. One official example is Bulbasaur’s Leafage, which can be used to add greenery to the landscape.
Bulbasaur is a dual Grass/Poison Pokémon and the first partner listed in the National Pokédex. Its seed-backed design makes it a natural fit for a game mechanic involving plants and habitat creation. The Leafage example is not the same as Bulbasaur’s signature ability; it refers specifically to the move being used in the environment.
Other Grass-type Pokémon, including Chikorita, Rowlet, and Sprigatito, can make this fact seem interchangeable. However, the official Pokopia description names Bulbasaur specifically when explaining the greenery-building use of Leafage.