These a not zigbee and you need to connect the devices to the LWRF hub.
I have the gen1 dimmers and sockets connected to my HE hub via an RPi.
If you do a search on the forum for lwrf you should find the post.
Their light dimmers and switches are brilliant, I had the Gen 1 for many years along with SmartThings, and as @bobbles states, you need an RPi, or some other always on PC to use them, but they do work well.
The downside of Gen 1 was only one way coms, so if you turn the dimmer or switch off, at the device, the hub doesnt know. Gen 2 will do this, although I'm not sure if it will with HE?
I'm awaiting delivery of two Xiaomi switches, they arent dimmers (we dont really use dimmers that much). And support switched live, so fingers crossed they work ok. I'll let you know how I get on if you like?