Hello!!, my name is Alejandro, I'm from Spain and I have been working on something quite similar to this project. I would like to contribute to reach a final design. What I have done until now is a prototype board similar than yours and I would like to add a top board with touch buttons to fit into Livolo glass panel switch.
https://es.aliexpress.com/store/product/Free-Shipping-Livolo-Luxury-White-Pearl-Crystal-Glass-151mm-80mm-EU-standard-Double-Glass-Panel-VL/500715_1684198410.html?spm=2114.12010608.0.0.6cyWwJ

And try to do something like this also including ws2812 rgb led for touchpad and a small speaker just to sound someting when touch the button.

https://z-uno.z-wave.me/projects/sensor-wall-switch-based-on-livolo-glass/

My development is based on ESP8266 without rf communication but as I have progressed I have checked that Wifi connection is a complex system compared to rf so I am thinking to change to arduino or esp + nrf.