Just to report: I can confirm Ewelink 2 channel Zigbee and RF relay module is working with ZHA.
It is not confirmed as working on blakadder.com yet, I already tweeted to Blakadder couple days ago, but till he puts it on the list people searching for confirmation can see it here.
Relay module adds easy to ZHA when in pairing mode, this is the module:
FYI, they also have a 4-relays model that says it supports “Zigbee 3.0” so strange if it is based on CC2530 or CC2631 as it don’t officially support Zigbee 3.0?