→Alt forms in Home Dex
Form differences sync to Home's dex IF you have a pokemon of any form deposited in Home and you have the form difference you want to register registered in a gen '''7''' game (not Gen 6)
Vililion Garden deposited in Home
Vivilion Fancy registered in Gen 7 game
Vivilion Fancy registered in Home dex
For some reason this does not work if the Vivillion Fancy pattern is only registered in a Gen 6 game, even if that means it's registered in the Bank dex. It also applies to Pokémon who have an Alola dex entry, like Furfrou. It didn't register Furfrou forms Home until I registered it in UM, even though I had it in OR/Bank's Dex
You can also register forms by depositing them if applicable.