The guest access of FRITZ!Powerline can only be used with a FRITZ!Box.

In a FRITZ!Box home network, the guest access of the FRITZ!Powerline device can provide an additional guest network. The guest access cannot be used with routers from other manufacturers.

If your router has its own guest access function, you can use FRITZ!Powerline to increase the range of that guest network. To do so, connect the FRITZ!Powerline device with the router's guest network. Note that in this case, the FRITZ!Powerline only expands the router's guest network and not the router's conventional Wi-Fi network.