Fibaro FGS-222 Dual Relay (ZWN-RSM2 device type) - WORKS!

Glad to hear it.
Im using “Fibaro FGS-222 Dual Relay” by Pukkahq

but I’m actually just about to write one myself so it has child devices (I.e. separate devices which can then interface with Alexa and CoRE). Currently it is quite difficult to arrange and requires a smart app but my solution will not need it. Feel free to install as you see fit, but then perhaps give my version a go if you fancy.