Git log is a special command, it uses a pager and it seems the PowerShell ISE hangs when you run into that kind of commands. If you try creating a script relying on running git log in whatever form, you won’t get anything.
The workaround is not the very best, but it does the trick:
$logcommand = "git --no-pager log ... [> file.ext if needed]"
Other commands like git diff are not affected by this. This made me lose quite a bit of time this morning…but I am happy to be unblocked now.