Toggle Post Process

How would I make a togglable outline effect on actors that are in games like Dues Ex or Dishonored. I’ve got the outline working I just don’t know how to toggle the effect on other actors in the world.

assuming your doing through something like a post process material you will need to get a reference to the post process or the the player camera then you just need to set the settings. for example in the picture below i modify the tint of the post with a button press.