Community members have been working on the lightify dimmer switch, and then are now several different device type handlers that work with it.
The non dimmer is on Osramās official UK products list, so it should show up in the UK eventually:
Meanwhile, for the UK there is a battery operated zwave switch available from multiple brands (popp, devolo, and Z wave.me.) Which is working very well thanks to a community created device handler. While not designed to fit over an existing switch the same way the Osram does, there are community members that have either just put a box over the existing switch or actually 3-D printed some very nice looking frames for it. Again, discussion in the forums. I would look at that as a UK option.
Blanking cover project for the Popp:
You should also check the UK lighting FAQ for other switch ideas.
In the US, the new Linear smart switch cover which is a similar design to the Lightify seems to be working well and there are other options there as well. But itās not available on the UK zwave frequency.
Instead of using the forum search, I recommend using google with the search term ācommunity.smartthingsā and then whatever youāre actually interested in, such as a device name. That should turn up most discussions.