Sorry I'm late. I added an issue to track a similar feature:
https://waffle.io/badlogic/spine-internal/cards/582ba04ac4f4485f0040f881
That still may not help you, since you want to duplicate a path, bones, and path constraint and keep them all working in the copy. It's probably best to duplicate the bones and path, then create the path constraint manually. That just leaves the animations. You can copy and paste the keys. To target different objects, select the duplicate objects before pasting.
As for a hacky way, you may be able to export to JSON and then edit the JSON.