How to self-host Fonts and change theme

Hi, in Germany we have a lot of trouble because of Google-Privacy Violations. We have to remove google fonts api calls and host them locally to prevent law problems. Whats the best way to remove the google api calls from your theme (music club) and host the needed fonts locally? Which theme files have to be changed? Much better would be an update of the theme, where I could select the local path without overwriting theme files. Is such an uptade planned to fit german law?

Thanks in advance