About AP Client Isolation
Enable the client isolation option on an SSID to prevent wireless clients from communicating directly to each other on the same AP, different radios of the same AP, and on different APs. In addition, for APs that run firmware 8.6.x or higher, wireless clients also cannot communicate with wired-side hosts on the same network.
Client isolation is useful in typical guest Wi-Fi access deployments to prevent communications between guest clients.
To enable client isolation on an AP, select the Enable client isolation check box in the SSID settings. For more information, go to Configure WatchGuard AP SSIDs.