We do plan to eventually add FSM and HTN implementations, but it’s not going to happen anytime soon. If you wanted to do that I encourage you to reuse our BrainComponent just like our BT implementation does. If you ended up writing something yourself it would be awesome if you could share it via github PR 
And let me know if you run into any issues while doing that (the HTN part, not the github 
)
Cheers,
–mieszko