You can manually control the movement if needed, it is defined under specification on Manual Control.

However, in AnyLogic transporters only move "forward". If you want to rotate the animation only by 180 degrees just for the purpose of presentation, you can rotate only the presentation items; no need to have it really go backwards. I have done this before with trucks; when they go in reverse it is still just a normal movement from A->B, however I rotate the 3D object so that it looks like it is in reverse.