I know this is late but you probably found https://nostr.watch/relays/find
You can check the website GUI for relay details or via API
This URL will return all relays that support nip #5.
Discussion
Wow, there's so many! Thx for the link
Probably worth looking here if you haven’t yet.
I just realized you may have meant a list of relay software which would be here along with a lot of other stuff.
Awesome (pun intended) thx