Question about TP-Link Re450

Also works as a LAN access point, but the firmware must be updated to V4 Build 230213. Then set "Operation Mode" to Access Point Mode and connect to the router with a LAN cable. A different network name is set up, but you can set this manually (for 5 and 2.4 Ghz) to the SSID and password of the router. Then you don't have to change WLAN and Sonos etc. work, where all devices must be on the same network.

I am not a network professional, but in my opinion this is a pure repeater that needs a router as a source. The LAN port is only intended to connect wired devices that do not have an integrated WLAN receiver.