Using the GPA PowerShell cmdlet Move-GPRMigrateGpo only makes a copy of the GPO in the destination category in the same domain rather then 'Move' as the cmdlet name implies. It should not be called 'Move' unless it actually moves the GPO rather than Copy.
Taking it a step further, there really needs to be 2 options since it is also for categories not just domains. "Move-GPRMigrateGpo" and "Copy-GPRMigrateGPO".
Currently in order to move multiple GPOs between categories, I have to revert to VBScript GPA methods to execute oGPO.link to link the same GPO to the new category since I want the actual GPO not a copy, and then oGPO.Delete to delete the link to the original location of the gpo. This is the only using a script to simulate a Cut and Paste of a GPO in the MMC.