Edimax EW-7811UAC doesn't see any 5GHz network

I can see that it’s getting what seems to be the correct driver (8812au) and successfully connects to channel 6 (2437 MHz).

It might be worth installing CRDA at this point:

sudo apt-get update
sudo apt-get install crda

Then edit /etc/default/crda and set REGDOMAIN=ES. Save and reboot.

You need to be sure that 2.4 GHz and 5 GHz have different SSIDs. Then run

connmanctl
scan wifi
services

If that fails to see 5 GHz, try to connect through ethernet cable, reboot and repeat the wifi scan. You might also need to run enable wifi in this case.