I am looking for a smart solution to add dimming capabilities to our foyer lights that can be controlled by 3 on-off switches. Here are how they are wired, based on (somewhat extensive) tinkering with a multimeter. Overall, there seems to be a first switch that takes the live wire, and then traveler wires are used to transfer that live (based on switch position) to the downstream switches. I am almost certain that I have the neutral wire after the bulbs available in the gangbox of that last switch.
I prefer a smart dimmer relay over a switch because this way, I get to keep the existing look of the switch (I don't care much for the "dimmer" functionality on the switch itself, but on/off should work). If I do have to go with a switch, I would ideally just try to replace the middle switch because it's the only switch in its box, and then it can look a little different I guess.
So, what are my options? So far, I have tinkered in trying to get a Shelly Dimmer 2 working but with no luck. For additional reference info on my smart home - I am in the US, I use Home Assistant and have both Z-wave and Zigbee environments running.
https://preview.redd.it/tifru77b9swb1.png?width=2633&format=png&auto=webp&s=a35b5b04d3c940eddc3761dc4067b56f13b4ec69
Why cat5e? I was under the impression that the cost difference between cat5e and cat6 was negligible nowadays, but maybe someone will comment on that