Have found a tuto here Bosch water sensor BWA-1: How to set up using install code? - #7 by sbonfert
Except now you don’t need to re compile code
The issue is here Bosch Smoke Alarm II · Issue #6421 · dresden-elektronik/deconz-rest-plugin · GitHub
But all have tried on conbee 2, IDK for conbee 3, but from other devs there is no reason for it work differently.