Is the PUN add on for UCC of any use to Behavior Designer? I'm not using UCC as I needed a custom controller, but I am using BD to run virtually everything else so I'm looking for the smoothest path to add networking.
PUN uses a client oriented architecture so what you would do is have the master client run the behavior tree logic and then sync the transform/animation state to all of the clients. The other clients don't even need to know that the character is an AI agent and Behavior Designer doesn't need to know that it is on the network either.
The tricky part is figuring out what to do if the master client drops from the game. In this case a new master client is selected and they need to resume in a state that is similar to the state that it was in when the original client dropped.