Add git-profile-manager to the list

[dm3ch]

https://github.com/dm3ch/git-profile-manager

This tool does the same thing as git-user add-on.

When you set user using git-user - you are just copying profile setting to local repo config.
Tool referenced above works different way - it includes profile config to repo config, so when you'll change profile user it "would be changed" in all repos it is used.

Also this tool supports setting profile for all repos that exists in some directory (using IncludeIf git functionality)