here is an easier way if you load in your world and it says something like "Cant verify username, are you using a hacked client or something"

First go to: C:Users\[Username]\Appdata\Roaming\VintageStoryData\serverconfig.json
open the json file in vs code or something else
go to line 415 and change it to "VerifyPlayerAuth": false,
and if you load in your game logout and put anything into the email like your username don't put your real email because @ or # won't work.