In my case, I created an emuMMC with Hekate 4.6.0 (my sysMMC, which I used to create the emuMMC, was on 21.0.0, so the emuMMC is also on 21.0.0). After creating it, I formatted the emuMMC system to completely detach it from the sysMMC.
Then I removed the PRODINFO data using NxNANDManager (I...