I am using three MM8108-EKH19 set up as 802.11s mesh. The easiest way is to use the Wizard. You set one device as a Mesh Gate with uplink to network. You set the other devices as Mesh Points using the same mesh ID and passcode as bridges. You do not need an AP. This does form a network, although I question that it is really behaving correctly as mesh. The MM User Guide helps.
We do not yet support mesh on MCU driver. But it is supported in the Linux driver. @PNW describes how to do it on the EKH19 platform which is an OpenWrt (Linux) based system.
I’m based in Europe, and as far as I’ve seen the EKH19 is not being shipped to EU. Is there any products I could use in Europe the test the 8101 chip with mesh?