Used 'Clone Device' option on device definition, it will add new device into list with appending '(edited)1' string.
select this clone device: press 'Next'
select this clone device: press 'Next'
select system image as per your requirement: press 'Next'
select 'Show Advance Setting' scroll down: in 'Memory and Storage' choose 'External file' (which is disable/gray-out in actual device but available in clone device) keep entry empty.