Forked core component - invalid handler specified

Hi! I would like to install an official integration as custom, so that it does not update when I update the core. This is because I make some edits to one of the configuration files of this integration to make it work better for me, and I would prefer not to have to edit it after every update. Is this possible? How to do it? Thank you!

I was able to create the custom integration (GitHub - AlessandroTischer/tuya_climate_mult_edit: This is a fork of the core Tuya component. Edited some climate.py multipliers in order to make thermostats display correct values), but the config-flow doesn’t work. Any idea?