I don't know if this helps.
I installed the plugin like this:
bin/plugin -i license -u file:/routetolicense.zip
the same for watcher.
If i try with:
bin/plugin install license
i get this error:
-> Installing license...
Trying https://github.com/null/license/archive/master.zip...
Failed to install license, reason: failed to download out of all possible locations..., use --verbose to get detailed information