Virtually any non-battery powered device acts as a router. There are some exceptions, such as the Sonoff ZBMINI-L2. So you can use any Zigbee that is recognised by eWeLink. They could be IKEA light bulbs. As long as you don’t turn them off with a regular switch, of course. Small and discreet are the Sonoff ZBMICRO adaptors. I have one and it works very well. It has several other advantages, by the way.