>How does Dino compare to Conversations when it comes to XEP support?
It may not be on par, but it's more than "good enough" and nice to use imho with working (video) calls and encrypted group chats etc.
This tool is only useful if you know what XEPs actually matter, which is not most people (nor expected to be!).
https://xmpp.org/software/ is a better resource for most people, as it provides the compliance filters (each software entry being either "core" or "advanced" in different categories, depending on e.g. whether you want a web/mobile client, etc.).
As you can see, Dino is pretty up to date: https://xmpp.org/software/dino/
Conversations, for comparison: https://xmpp.org/software/conversations/