pidgin

I have it and have used it in the past, I quite liked it.  I think I used it as an alternative for MSN Messenger, but it supports multiple protocols such as IRC and XMPP.  I don't think it supports the newer OMEMO encryption on XMPP, but I've not checked that in a while.

It sounds like an interesting project. I will look into it. :V

I haven't heard that name in over 15 years, used for a while but then switched to emesene.