It's a simple 1 plus.
The light I'm using has a control board. You normally don't interact with it, but I managed to expose some pins and added some optocouplers. I can now control the brightness of the light with 2 outputs of a microcontroller.
The Shelly can be connected to mains, has a switch input, a relay for the light itself and has io 0 and 19 available on the outside. So hardware seems perfect for this application.
I was planning to write my own software. But if I can do it out of the box + script, it will make my life much easier. I would only need an mqtt topic connected to each io pin.