Cosmo CRTDW Thermostat - encryption

By the way, be sure to also read this → Generic best practice tips on improving Zigbee network range and general stability · zigpy/zigpy Wiki · GitHub

Oh, IMHO, for about $20-30 might just buy a CC2652P adapter to test both ZHA and Zigbee2MQTT

https://community.home-assistant.io/t/iteads-sonoff-zigbee-3-0-usb-dongle-plus-model-zbdongle-p-based-on-texas-instruments-cc2652p-20dbm-radio-mcu-now-sold-for-19-99/340705

and as you can later migate and re-use any CC2652P adapters as Zigbee Router (signal-repeater/range-extender) by reflashing its firmware you might as well also pre-order Home Assistant SkyConnect USB Stick as well for another $30-40 since it will also enable support for Thread/OpenThread (and Matter over Thread) in the future.

https://community.home-assistant.io/t/home-assistant-skyconnect-usb-stick-announced-will-be-compatible-with-both-zigbee-and-thread-including-matter-chip-over-thread/433594/