I have two raspberry pi and each have separate 10 inch display. One raspberry is in Engine room and another is in bridge of the ship. Temperature data from engine will come to Master raspberry pi (Engine Room). Engine room display will show the temperature. Display of slave raspberry pi (Bridge) will show the same temperature reading of engine. both raspberry pi is connected via a LAN cable.
Problem: How to share same display in two raspberry pi display?
There are several ways to do this. The way I've done it is to simply use sockets to send the reading from one to another. it's less than a page of Python code to do so. I used PyGame for presentation. Another way would be to use one line of code to make a webserver and use a browser. (http.server).
Or, you could use RealVNC to duplicate the display. Python works very well for "one offs" and prototyping with minimum coding.
Our https://pvbrowser.org (besides others) runs on Raspi.
It could do the job.