I’ve got 2 Sonoff SNB-01 buttons, and neither of them work in HA.
I’ve tried pairing with a Sonoff Bridge flashed with Tasmota, and also a zigbee2mqt USB dongle. They appear to be paired, but in fact are not. The only entities I get are for battery state - but not the switch state. A Sonoff motion sensor and door/window sensor paired and work fine.
implies that there is a particular way to report issues like this, using a template, but I can’t find a specific page to do so!)