I believe you can achieve this by using transitions between frames, with the Smart Animate mode.

Instead of having one tall frame, you'll need several frames with a smaller height:

Notice, in the layers panel, that the green rectangle is already present on Frame 1. It is invisible because it has been moved "out" of the frame even though it is inside. This is important because Smart Animate will take the position of Green Rect from 1 to 2 and make it move on that specific path.

Let me know if this helps and if you need more help. Good luck!