The shader you put together does absolutely nothing the tutorial shows.
Mainly I think this is because of the use of the transform instead of a multiply.
First. HOW you made the model matters.
the UV could be flipped in the material (the multiply -1,1 node) OR, they could be flipped in the UV of the model.
IN unity you have a Y up coordinate system. in unreal we have left hand coordinate system (z up)
The whole shader starts off with the “assumption” that the UV plugged into WPO or World Displacement generates a camera facing version of each face.
This isn’t true in UE4.
Really Not sure how to get that part going.
To rotate the position of each face you need, at the very least:
The Pivot Point of each face (given by the world location of the vector field transformed texture coordinate nodes transformed to worldpsace)
A rotation axis. where the camera and Atan2 come in to figure out the rotation to apply.
if you have those 2 values, plugging them into a Rotate about Axis along with 0,0,1 as your normalized rotation will yeld a “billboard” like effect that follows the camera.
I’ll try and take a stab at this tomorrow because it’s an interesting effect. Wouldn’t hold my breath on it working as easily as it does in Unity though.