At the University of Kent, Skylar Kelty created a drag and drop between courses feature (local plugin)
The principal aim was to assist with course rollovers, encouraging the best activities in the previous course being moved into the new one without bringing all of the other content.
I have found tracker issue https://tracker.moodle.org/browse/MDL-47032 which says this is in development for 2.7, but not sure this is progressing.
If keeping to the same Moodle instance, it wouldn't be necessary to duplicate file resources, just migrate the data minus user information.
It can pretty much be based upon activity backup and restore in core Moodle with the right parameters set (don't copy users, grades, groups etc to the new instance).
Should we have a new tracker? Does anyone agree? The Royal Veterinary College is too small to support and maintain hand built plugins, so it would be good to see this move into core.