Rasa X doesn’t yet support v3 of Rasa Open Source so that will be why you’re having issues. You also need the latest version of pip installed it seems. Compatibility Matrix
I’m also struggling to get Rasa X working on the latest supported version of Rasa Open Source though http://forum.rasa.com/t/rasa-x-1-0-1-compatibility-issue-with-rasa-2-8-2-2-8-17-models