The UART to TCP bridge needs to talk to the same UART device /dev/ttyS2 as used by the Tuya integration and my understanding is that Linux prevents the same device port from being used by multiple services at the same time. I’m not sure if there are tools out there that can create virtual interfaces for the same hardware port and let multiple services talk to it. I’m also not sure how the Tuya binary will deal with the messages and responses not originating from itself.