So I use NordVpn Onion connection and establishing a Tor relay (when starting the browser) takes forever (10+ minutes) something is obviously wrong here. What can I do to speed this up?
There’s no real foolproof way on doing that with those servers I think. You could try the general troubleshooting of changing server, changing connection protocol, etc. In general though connecting to standard servers and using a TOR browser should already be the same as connecting to Onion servers so you shouldn’t need to connect to them really if you’re using TOR.
But maybe you can contact NordVPN support for more help about that. I’m sure they have more knowledge regarding the topic.