Just thought I'd try using UIFlow 2.0 with my Atom S3 before I go down the Arduino rabbit hole.
https://docs.m5stack.com/en/unit/zigbee

I noticed in the configuration panel on the left, it only had Pa.HUB, ENV, ENVII and ENVIII, not the Zigbee unit with the blue grove plug. So I might assume this unit is not supported in UIFlow 2 ?

I tried using the UART and got as far as:

from hardware import *

uart0 = UART(0, baudrate=38400, bits=8, parity=None, stop=1, tx=2, rx=1)

while True:
    if uart0.any():
        print("\nFound Data:", end="")
        print(str(uart0.readline()))
    else:
        print(".", end="")
    sleep(1000)

But given how proprietary the CC2630 is, I expect that's as far as I'm going to get.

I found these examples here in C:
https://github.com/m5stack/M5Stack/tree/master/examples/Unit/Zigbee_CC2630

.. which do not show how to pair sensor and read data from them. Has anyone got examples of how to do this with the UART interface ?