Need help creating/copying an effect.

I don’t know the name of the technique, but here’s a video of it from the game Path of Exile.

I’m primarily trying to create this in Unreal Engine 3 for Killing Floor 2 modding. So whatever help I can get here, I’m going to try to translate it into UE3 unless there are features I need which are only found in UE4.

I think the idea is having a transparent image hidden over the entire screen, then having a material on an object to reveal said image. Kinda like a detective movie where looking through a special piece of glass would reveal secrets scribbled on a wall.
Or something like that.
The closest I’ve gotten to this is using a bump offset on a 2D texture. This method is used for creating fake interiors behind windows. But it also creates a curved look around the material edges, and can’t be freely applied to any model without getting warped even further because of the model UV wrap.