Question about Ubiquiti UniFi AP-AC-M MESH

Quentin's answer is somewhat inaccurate. You have to configure these APs via a cloud key. But back to the actual question. Yes, all SSIDs are also available on the mesh AP and it can also use both frequencies simultaneously. I have such a thing in use myself and am very very satisfied. As with all Unifi products from Ubiquiti.
I use the Mash AP as an extended "arm" for my conservatory and large terrace. The mesh is connected via Powerline.

Hello

If configured via UniFI, all networks should be able to be transmitted.

Greetings