you need to send Postcards from the mobile game toScarletandViolet. Sending a Postcard between games will reward the player with Gimmighoul Coins, and other items, inPokémon Go.
To catch Gimmighoul inPokémon Go, you will first need to connect your mobile game to your copy ofPokémon ScarletorViolet. This will let you send Postcards fromGoto your Switch, thus unlocking the full contents of this crossover feature. Related:How to connectPokémon Goto Nintendo Switch Once...
As a tie-in for the Gen IX games, Niantic and The Pokémon Company have made it so Gimmghoul (Roaming Form) can only be captured inPokémon Go. And to evolve it, you need to send Postcards from the mobile game toScarletandViolet. Sending a Postcard between games will reward the player...