[JepZ]

Sadly I don't. I have mine running since a while, and some things might not be state-of-the-art anymore.

The server doesn't really have to support end-to-end encryption as that is part of the clients (in fact, there are some server-side extensions which have to be present, but those are mostly enabled by default).

Afaik, the default ejabberd configuration is very close to what you need, and there is just one part that you have to remove to enable OMEMO [1]. I don't understand why but recently the ejabberd devs introduced that part to their default configuration which makes it harder to use end-to-end encryption.

Nevertheless, if you are very interested in a detailed guide, I could write one as I am thinking about setting up a secondary server as a testing environment.

[1]: https://github.com/processone/ejabberd/blob/master/ejabberd....