I used Keynote, especially the magic move function, to create the animation. A magic move is transition that creates the effect of objects moving from their positions on one slides to new positions on the next slide. Then you can export the keynote file as a GIF.
It was made with keynote with the magic move between slides. Maybe @yazhuo can share the file.
@Hrun0 @portpecos Sure, I'd like to share the file if anyone needs it.