The HDMI port on my Mokin MOUC1801 was working just fine on the monitor I was previously using, but when I switched to an HP Z27X monitor, the Mokin won't pass HDMI at all.
Other USB-C hubs in the house have no problem with the Z27x, using the same laptop and the same cable. So the problem is definitely isolated to the Mokin MOUC1801.
I want to continue using Mokin because your adaptors have that handy pass-through power feature.
Do you possibly sell another adapter with better HDMI support?