Any good AI middleware?

Hi! Are there any good AI middlewhere worth looking into, that you can recommend? I heard about Autodesk Kynapse, but it seems to be gone - it has some interesting avoidance and group behaviours. I also googled something called Artificial Contender which has good concept of being able to train AI by playing the game, but project seems either dated, or not updated. I wonder, maybe there are some hidden gems or anything I might be missing.

I do not need anything that UE4 already has to offer - behaviour trees, navmeshes and pathfinging