The switching of a conveyor direction is atypically feature. In such a scenario you use an AGV, because the amount of items to distribute to different directions isn't certain for a given time. If you depend on such behaviour the legacy basic conveyor object has got the ability to change the direction. The legacy objects can be activated in the environment menu item of the main menu file. You find some more information in the older and previous forum at community forum. But the object isn't supported anymore. Maybe you can take a standard processor and add an animation that looks like a conveyor with switching directions or you can take a look at the Flow Nodes.
