Not sure that a user report would should you the empty branches and since there is no real ‘branch report” it may still require some manual effort.

found this set if Apis but not sure it’s what you need:

https://doceboapi.docebosaas.com/api-browser/#!/report/BranchDashboardEnrollment/BranchDashboardEnrollment_report_v1_branch_dashboard_enrollment_id_view

Using your favorite automation tool, this will get you all of your branches and descendants:

https://YOURDOMAIN/manage/v1/orgchart?search_type=1&flattened=true

For each branch ID returned, you would want to retrieve the number of users:

https://YOURDOMAIN/manage/v1/orgchart/BRANCHNUMBER/users?page_size=1

The “page_size=1” parameter will return a single user (in order to limit the amount of data returned). The only part of the return you’re interested in is under the JSON path data.total_count

This will provide you with the number of users for that branch including subbranches.  You’re looking for that number to be zero.  At that point you could use the Batch deletion of branches endpoint to remove them this way:

https://YOURDOMAIN/manage/v1/orgchart/batch

{

  "items": /

    {

      "id": BRANCHNUMBER

    }

  ]

}