The problem specific of a soccer ball is the fact that it has no edges and that being round, if you want to make it truly 3D you should be able to show the hidden parts of it while hiding others, also it mostly retains its shape (except if you're squashing/stretching it) so the 2.5D deformation isn't really useful.
If you want to learn this effect I recommend objects that have a hard edge or that are at least soft, so the deformation doesn't look weird/unnatural.
Here's the topic that goes more in depth on the specific example that you posted: two girls animation.
Here's a topic where you can download an example project with a 2.5D cube effect: How to turn your 2d character looking 3D
I think you also need to check the weights on your image, if when you move the bone you don't see changes, maybe they all got set on only one bone: Weights - Spine User Guide To fix this you can select all the bones in the weights panel and click auto, or you can manually paint the vertices.
