I'd recommend the SLZB-06 (not 06M) instead though. It uses the same TI chip as the Sonoff, but is more flexible as you can use it via USB or via Ethernet, and it supports Power over Ethernet. It also has a web interface for flashing the Zigbee firmware (source: https://www.facebook.com/groups/HomeAssistant/permalink/3677951979142812/)