Yes there is a complex way to migrate user sheets as well:
- approve all sheets (remember which sheets got approved by this action)
- publish all sheets (remember which sheets got published by this action)
- Export the QVF
- Import the QVF somewhere else
- disapprove the private sheets
- unpublish the private sheets
Note: you can do this with all kinds of private data (e. g. bookmarks, stories)
The UI does not offer all of this functionality, but you can use the REST API.
Not very straight forward, but that's a workaround that works for me.
in general you can get information on the QRS (Qlik Repository Service) on this page: https://help.qlik.com/en-US/sense-developer/1.0/Subsystems/Qlik_Sense_Repository_Service_API/Content/QRS%20API/Repositor…
However you might need to get additional call to get to know by using the dev tool of your browser to see which addresses are used. I did this and found the following undocumented methods:
Hope this helps