Yeah you need a separate dongle. The ZBDongle-E from Sonoff is pretty cheap on AliExpress. Cheaper than the official Home Assistant ZBT-1 dongle Nabu Casa sells. Unfortunately running both Zigbee and Thread on one antenna doesn’t work very well even with the dongle from Nabu Casa.
I only just bought a zigbee USB antenna, and 4 smart plugs. You’re saying I need a second USB antenna dongle for thread?
Yeah you need a separate dongle. The ZBDongle-E from Sonoff is pretty cheap on AliExpress. Cheaper than the official Home Assistant ZBT-1 dongle Nabu Casa sells. Unfortunately running both Zigbee and Thread on one antenna doesn’t work very well even with the dongle from Nabu Casa.
Only thing with the ZBDongle-E is that you need to flash it yourself to run OpenThread via this website https://darkxst.github.io/silabs-firmware-builder/ it’s not hard though.