Model :

Hardware Version : Not Clear

Firmware Version :

ISP :

Dear all,
I have a problem which I can't solve with my limited knowledge of the power line system.
Here is my configuration

I have a router connected to a Powerline 1, then a bunch of other devices connected to Powerline 2 through an ethernet switch.
Then I have a wireless capable Powerline 3, a WPA4220, which I want to use as an access point with a different SSID than my "main" wifi network, intended for guests, who have a room far away from my main router.
I have enabled Wireless AP isolation on Powerline 3 but when I connect via wireless through it, all the devices connected via ethernet to Powerline 2 are still visible from the wpa4220 clients and I don't want that. Basically I don't want the devices connected through the wireless network generated by Powerline 3 to be able to see any other device in the network, wireless or ethernet connected.
A solution would be to have Powerline 3, the WPA4220, to be able to connect to Powerline 1 but not to Powerline 2, if that is possible, or to have a complete, ethernet AND wireless isolation of Powerline 3.

Is that possible?

Thank you!