Visual Studio Code: Use Beyond Compare diff tool

Try this extension:

GitDiffer – Visual Studio Marketplace

It works for me on Windows 10, here is my .gitconfig settings

[difftool "sourcetree"]
    cmd = 'C:/Program Files/Beyond Compare 4/BComp.exe' \"$LOCAL\" \"$REMOTE\"
[mergetool "sourcetree"]
    cmd = 'C:/Program Files/Beyond Compare 4/BComp.exe' \"$LOCAL\" \"$REMOTE\" \"$BASE\" \"$MERGED\"
    trustExitCode = true
[merge]
    tool = sourcetree
[diff]
    guitool = sourcetree