The Mx10 feedback widget with screenshot markup looked awesome! We utilize JIRA for ours with a custom action since JIRA supports SLA tracking. It would be awesome if Mendix tweaked this widget to allow it to be pointed at JIRA so we can take advantage of the screenshot markup.
Looks like JIRA implementation is in Beta
https://docs.mendix.com/developerportal/project-management/jira-connector/
While not a perfect solution, you could use the following module to get the feedback inside your mendix app instead of the mendix sprintr and then use the Jira REST api to push the feedback to JIRA.
https://marketplace.mendix.com/link/component/211652