How to sync fonts across Macbooks? Extended question
Implemented a shared font resource may not be as easy as just syncing the entire font folder. 

The user font folder may contain font management files, such as encodings.dir, fonts.alias, fonts.list, fonts.dir, fonts.scale. 

One of these files, fonts.list, contain full pathnames to the fonts, so if the user names on the shared machines are not the same, this will confuse the font manager. 

Also, like many parts of macOS, font resources are cached, so violent changes to the Font folder may require emptying the font cache.

You may be better off just copying the fonts library to each computer and then managing them locally with FontBook, or with a third-party font management app. 

You should also check the EULA of the fonts you're using to confirm that you are operating within its terms.