6Ghz is not a good choice for wireless mesh backhaul. Penetrates walls/floors/ceilings poorly. The only mesh system I've found that works well is wired backhaul.
I do have a 6ghz card in my system. It's an 8devices Pineapple 6, and I had to get an adapter to interface and also move to the front of the system. Probably will not work with hw offloading, but is 4x4 which is nice.
