TP-LINK Powerline device doesn't support Mu-Mimo and there is no configuration.

Yes, you can add a additonal powerlien device to the network, but on the market, ticket powerline device is normamly sold by two device together, one adapter and one extender. I found a FAQ on...

Hey Man, here is TP-Link forums, if you have a netgear extender, you may need to ask support from netgear:)

Hi， the function of extender is not used to improve the speed, because it need to communicate with your main router ,and the device which connected to it, the speed will be slower in some degree. For...

Hey, If you disable the security for the 5G connection, can you join the network? Or change the encryption type to TKIP for a try？

Currently, it doesn't support use multiple accounts to control the same device.