Can two USR-TCP232-304 (RS485-to-LAN) devices work in bridge mode?
This is achievable.
Please refer to the documentation in this link：
Transparent transmission between USR Serial to Ethernet products: https://www.usriot.com/download/M4/Transparent-transmission-between-USRIOT-Serial%20to%20Ethernet-products.pdf
The document uses a USR-TCP232-302 and a USR-TCP232-304 to establish a TCP connection. You can use two USR-TCP232-304 settings directly for your application. The setting method is the same.