Set material from actor reference?

I’m trying to convert an actor reference to a static mesh actor reference, or something like that so I can change the material properties. Basically I’m using sphere overlap components to detect nearby mesh walls, then making them transparent. I can do it by turning them all invisible, as the set actor hidden in game node works with arrays of actor references. However I can’t find a way of editing the material of these actors. Any ideas?

If somebody else also has this issue, I got this working by using Cast to StaticMeshActor > Target Static Mesh Component > Set Material. Then in Cast To StaticMeshActor, link ‘Object’ to your desired one.