I'm not sure exactly what You are asking as your post seems to contradict the title.
What I have done is go with your title & use gravity (Physics) to move the square. Here is the modified file:
dnd-new_scene-v2.hype.zip (124.2 KB)
Clicking on the red square starts it sliding to the grey one, and when it is inside, transitions to the new scene. As shown in the video snippet just below:
I used the Physics Inspector to control the slide & the stopping of the red square. You can read more about the Physics Inspector here.
The Timeline has an action to jump to the next scene. Note that when You assign an element to be "Dynamic" or "Static" You can set various Physics properties of the element in the Timeline - as shown in the screen shot below: