And would like to hook both of these Arduino's (running at the same time) to the CrowPanel and be able to update the panels UI from each board.

Currently im testing with a single Arduino (the giga) which is hooked to the CrowPanel via UART2 (RXD/TXD) and im sending data back and forth with the UI (using SquareLine for UI), pressing button on UI will send signal to Giga and when a sensor hook to Giga reads a value it will send that value to the UI, everything is working.

Now i would like to:
Add the Nano to read a Roatary Encoder and update the UI with the values read.
And still use the Giga for other sensors and also have it update the UI.

Is this possible with the CrowPanel Advanced 7inch ESP32-P4 ?
Can i tie all (three devices) RXD, TXD and ground pins together and power each one from a different source and it will work ?

Any help, insight or pitfalls would be great.

Thank you...