I do this to separate personal and company repositories on the same machine, and it works flawlessly. An example config looks like:

~/.gitconfig:

```

[includeIf "gitdir:~/Personal/"]

        path = ~/personal.gitconfig

```

~/personal.gitconfig:

```

[user]

        email = {personal email address}

```

And you can have arbitrary numbers of "profiles" like this, as long as each is in their own directory.