I tried to figure this out myself but I couldn’t, I have 3 lights in my backyard that two of them are z wave switchs and the other one is a tuya, what I want to achieve is having one button to turn all three lights on or off at the same time, I was able to combine the two zwave ones together in a group and name it “Backyard Lights” but i can not add the tuya to the group.
If you want the switch to actually look like a light you can use this to create a new light from your switch and use that in Lovelace dashboards instead of your switch.
You can create a helper of type “Switch as X” and create a new light entity based on your switch. Then you can add this new light entity to a group (which is also available as a helper). It works just fine.