[Finn]

Find some function which calculates the angle between 2 points, then get the angle between player A and player B and check if the angle is equal to player A's facing angle. If it is so - do what u want.

Edit: Oh, you wanted to SET the facing angle? So calculate the angle and set the other player's facing angle to that. lol

You might need to make it OPPOSITE angle, so just do angle -= 180.0.