I will try to better explain my configuration.
I have a Vodafone Station router to which I connected my AR750S device via cable on the WAN port.
Then I connected my notebook to the LAN port of my ar7520 via cable.
I activated wireguard server and created the client configuration for my notebook, since the WIREGUARD VPN is active I can no longer access the UI 192.168.8.1, in order to access I have to disconnect the tunnel of my notebook (wg client).
Is there a way to be able to create a subnet and be able to access the UI 192.168.8.1 interface?