https://docs.gl-inet.com/router/en/4/user_guide/gl-mt300n-v2...

These devices have the wifi/ethernet bridge functionality being discussed, (as well as a bunch of other stuff) and are OpenWRT based. Built in openvpn/wireguard as well. We bought a bunch for our team way back when (IIRC they were < $20 USD then) Gl.iNet has other similar more powerful devices as your use case may need.