Pikachu is the Pokémon called Peakychu in Pokémon Pokopia after losing the ability to generate electricity. Peakychu is one of the special Pokémon Ditto encounters while restoring habitats.
The character is a variation on Pikachu's familiar identity. Electricity is strongly associated with Pikachu, so the loss of that ability gives this individual a problem that differs from the usual portrayal of the species.
Pokopia includes several named or unusual Pokémon with personal circumstances. Smearguru is an exceptionally talented painter, Mosslax has slept beneath moss and plants for so long that they cover its body, and DJ Rotom possesses a stereo system.
Peakychu should not be confused with Raichu, Pikachu's evolution, or with other electric Pokémon such as Plusle and Emolga. The name Peakychu points to Pikachu, and the game's story explicitly identifies the character as a Pikachu who can no longer produce electricity.