You cannot do H1 transfer
Hi,
If you have used EAD, you would have given up your H-1B status for good. You will be an adjustee. Hence you need to apply for fresh H-1B petition if you have to go back to H-1B.
By fresh, I mean brand new H-1B subject to the H-1B cap.
A h-1B transfer petition is done when you are on a valid H-1B status and transfer it to a new employer.
But who knows, USCIS may approve your transfer petition even if you have used your EAD. That is their greatness!. But legally it should not be.