in ue4 one sided planes used as collision results solid from a direction but totally penetrable from the other side. all meshes in crayta has volume so results solid from any direction. this is its a very usefull collider to have. fully implemented one side platforms are a different beast , but having in common the “one sideness” has come to my mind as another very interesting and still missing feature.
A resizeable collision plane mesh for one side collisions and or full one side platforms