To answer your question; I believe if you set the AI’s animation for on hit to be locked in place by using EnableRootMotion, example is attached:
That should prevent the character from doing anything else using animations for the time being, along with locking the AI or player in place during the animation, so provided you have animations setup for attacking, it should act as a stun or stagger period. At least that is how its working for me in my game right now. Both the player and AI on hit received or damage received play a hit animation, are staggered, and cant attack again until the animation is done. You could always shorten or extend the animation playtime to increase or decrease the staggering effect.You could also create a IsStunned Bool, and set that to true on character hit received, then use that as a condition on branches in your AI’s attack to make sure its not stunned or staggered before allowing attacks or other actions. Although that is just really for further control over crowd control effects in the future & the animations should handle that on a basic level without that bool being checked.