Split Screen post processing doesn't work

Making A multiplayer game and I want my effects to have this neat HighLight around my objects when players look at them. However, Post Processing is the only one that works best so far.Now in multiplayer, Players see the effects whenever any players look at an item. Thats a problem because I just want the individual who is looking to see the high lights. Not sure how to do this Since I am using line trace to activate and deactivate this. I am new so Im thinking line traces are for everyone at all times so Need some help.