Which two companies published Pokémon Pokopia?

Nintendo and The Pokémon Company published Pokémon Pokopia.

The two companies jointly appear as the game’s publishers, while development was handled by Game Freak and Koei Tecmo’s Omega Force. Separating publisher and developer is important because the companies responsible for making a game are not always the same companies responsible for releasing and marketing it.

Nintendo has published Pokémon software across its hardware ecosystem, while The Pokémon Company manages the broader Pokémon brand and coordinates its games, merchandise, media, and licensing. Their involvement places Pokopia within the official Pokémon game line even though it is a spin-off rather than a main-series adventure.

Koei Tecmo’s Omega Force is therefore not the answer to this publishing question. Omega Force is the development studio credited alongside Game Freak. Game Freak is also a developer here, not one of the two publishers named in the game’s credits.