I am trying to change a particle effect’s color by using a key press (K) in VR mode. I found this video (Unreal Engine 4 Emitter Parameter Instance for Changing Colors - YouTube) which was really helpful but uses a mouse press and is in third person mode. I am not that familiar with UE4 yet so I don’t really know what replaces the third person character in VR and which node I need in between ‘get player controller’ and ‘break hit result’ nodes.
this is the setup I am currently using.
You need to enable whatever actor you are in to accept input. Go to the actor’s Class Defaults, and under Input change the Auto Receive Input to “Player 0”.
Also, if you check out the VR example project, you can learn more about good ways to set up VR in general within Unreal. 
So I put the particle system in a Material Blueprint would I still be able to change the Auto Receive Input?
So I found the solution to my problem. First of I putted everything in the emitter blueprint it self and then switched some stuff around as well. Indeed changed the auto receive to player 0 as well. This is my bp now:
