warning: templates not found /usr/local/git/share/git-core/templates

In case of Source tree on macOS Steps:

Source tree Menu
Preferences
Git
Click on System Git under Embedded Git Version 2.2.1
Reset to embedded Git
Restart source tree

Create a templates folder.

In your case, it should be: mkdir /usr/local/git/share/git-core/templates

I was also getting same error warning: templates not found /usr/local/git/share/git-core/templates when I cloning repo in local repository then i found solution which solved my issue. I Added the [init] section to .gitconfig in home directory, so that it looked at SourceTree's git templates directory when cloning a repo:

[init] templatedir = /Applications/SourceTree.app/Contents/Resources/git_local/share/git-core/templates

Hope it will help you!.