@Fab1an According to the OneMesh website, your Powerline adapter will be compatible "soon" with a firmware update.

However, "soon" might be a few months, so...

@mocelet That's really disappointing of tp-link. I expected the devices to work together. The Powerline is pretty much useless if the devices don't switch the WiFi automatically when changing rooms. Anything I can do about that?

@Fab1an Well, it depends on how smart the device is. iOS devices usually change to another WiFi as soon as they detect it has better signal. However, Android devices try to stay as long as possible in the same WiFi and switch to another only when the signal is almost lost. Devices are to blame to a large extent, they could be more smart.

For those Androids that do not automatically switch by themselves, usually enabling and disabling the WiFi is enough, they will search again and connect to the best network available. It's not seamless but it usually works.

You can also use the same SSID name, password and parameters for both your router and extender networks. But again, it's on the devices' intelligence choosing where to connect and when to switch if necessary.

Network assisted roaming is not very common in home routers, that's a feature usually found on business access points for large spaces. It doesn't matter if it's TP-Link or other brand.

Seamless roaming has been a thing recently because of mesh systems, a technology that, again, is in its early stages in consumer communication devices.