Hello Patrick,
Have you looked yet at the JIRA API? https://developer.atlassian.com/server/jira/platform/jira-rest-api-examples/
It seems pretty straightforward to create an issue via an http request, so perhaps you can build a microflow that’s executed when you click the button, which will send the relevant data from your email object and create the issue on JIRA.
You can use the Call REST activity from your microflow, as described here: https://docs.mendix.com/refguide6/call-rest-action#general
Hope this helps!