I am using TP-Link AX1800 WiFi 6 Router V4 (Archer AX21) and extenders RE220 for my home wifi network.  Recently, I started using an RE220's ethernet port to connect some devices with only ethernet connection but no wifi.  In some cases, it is better to let the RE220 providing the ethernet connection operate in bridge mode to reduce the interferences in the wifi network.  After some search and experiments, I found what described here for RE200 also works for RE220. 

To set it in bridge mode, you can use whatever methods to set up the RE220 as a range extender for network. After sign into the webpage of the RE220 to serve as the bridge, you need first go to the subpage of /setting/EasyMesh to disable EasyMesh.  You can then disable the Extended Networks in the Wireless subpage so no RF signals will be transmitted from this RE220 and it is in bridge mode.  What I find interesting is that even I disabled both 2.4 GHz and 5 GHz transmissions, I still can access the webpage of this router from a computer on the local network.  The suggestion of "not completely disabling both bands" in the reply to the original RE200 posting seems unnecessary.