It's literally the same thing, but backwards
BUT, mt-card should be able to read gateway's emunand without needing to change anything
Followed this guide to change GATEWAYNAND into MTCARD_NAND with WinHEX.
But it failed.
When entering the system setting, it neither displays GW3D nor MT3D.
Maybe WinHEX is NG?
I'll try to recreate a new MT-emuNAND and inject the current GW-emuNAND to it later.
BTW, the current GW-emuNAND is a historial copy of a legit console's SysNAND before System Transfer.
So it's unlinked from SysNAND.