I’ve been playing AssCreed Odyssey as a stealthy archer and it’s solution to that particular problem seems to be attaching your location to each fired arrow; enemies within some radius of where the arrow hit are given a search target somewhere near your position when shooting. Add in some “It came from over there!” barks and it works pretty nicely
If you are far enough away there is a big hole in this wherein they can’t get to your position before their maximum-amount-of-time-in-search-mode timer fires off and they go back to their normal location and behavior, though.