In my playtime I performed attacks early which almost always guarantees a hit against the NPC with their inhumanely fast reaction times. I needed to make sure I was within the bare minimum range for a good hit though. Or letting them walk to me and attacking early.

Hit and run tactics I recommend or "hit and dodge" since I found that if they're not knocked down they recover within milliseconds and hit you before you know it, usually done after attacking once or twice. Or you could block which has a fair chance of fooling them if they think they can land a hit on you after you wailed on them after 2 good hits.