Author Selector is an addon available at all plan levels.
This allows admins and mods to change the author of a discussion, question, poll or idea.
The admin or mod will require the 'edit' permission for the discussion they are trying to change the Author of in order to proceed.
You can enable this by going to settings, then addons.
To change the author, simply click the cogwheel from either the Discussion list view or the discussion page itself.
This addon does not work with comments/answers at this time - only discussions.