With GDPR coming down the track I'm keen to dig in to my contact lists in more detail. I'm looking the ability, ideally through the UI, of reporting on, and searching for, contacts based on the date they subscribed to a given group, the method by which they were added to the group, and the status of their group membership.
Currently there is no reporting or search on group subscription history. But I do think the gdpr extension (https://github.com/veda-consulting/uk.co.vedaconsulting.gdpr) has a custom search which allows you to search the group subscription history.
Exists a subscription history extension https://github.com/MegaphoneJon/org.cpehn.subscriptionhistory which may fit your needs.