One year later... here I am. I tried all the methods mentioned in the previous answers but I still have problems with the integration of deCONZ.
I still get the "Couldn't get an API key" error.
The problem is that if I set the network type to host in the deCONZ template, I can't access the webUI. Vice versa, if I set the network type to br0 and assign an IP in the Home Assistant Core template, I can't access the webUI. If I leave the different network type configurations, both webUI work.
Can someone please help me? I really can't find a solution...
Here is my actual configuration: