Can an STM32WB55 with ZigBee stack programmed, join a network of XBEE modules from Digi? I am new to WB55 though I tried upgrading firmware etc.

[Remi QUINTIN]

There is no limitation as long as the XBEE module is configured for the same channel using Z09 key.

https://www.digi.com/products/embedded-systems/digi-xbee/rf-modules/2-4-ghz-rf-modules/xbee3-zigbee-3