Would come to be the same. Just change "how" "What" ^ ^

Your question is: Is there a difference between How about you? and What about you? or are they the same? The answer is yes, they are interchangable, yet 'How about you?' is the formal one of the two. I suggest you choose one and always use it in your learning process. Kind Regards

I am not finding a time when these are not Interchangeable. I am givving the green light on that.

It's the same meaning.