Nintendo of America has announced that an update for Pokémon HOME to support for Pokémon Scarlet and Pokémon Violet is coming in early 2023. You can bring the following to Pokémon Scarlet and Pokémon Violet:

Roaming Form Gimmighoul that you’ve caught in Pokémon GO.
Certain Pokémon you’ve journeyed with in past Pokémon games.

Source: https://twitter.com/NintendoAmerica/status/1630311815258284034