It work indeed have it found a time ago.. Just try to compare it with the regular 12mpx, you will see that is worse, artifacts and noise will occur.. Try ultra cam based on burial with the proper magisk module it has a dedicated 48 mpx mod, I couldn't make it work because I'm in miui pie stock rom..
Where did you test this feature before?
I haven't found this until parrot uploaded the new beta 7.3 gcam.
Anyway if you increase no of hdr frames then noise may reduce but there is no option to select hdr frame.
But comparison to stock camera , it works much better and no root is required for this.
I will compare with regular 12mp .