Want a chin/jaw reduction for vertical height but afraid of it projecting my jaw forward. Will this happen? (photo)

I have a very long chin/jaw (both sides are different). I'm now in my early 30's & have decided to stop acting like I don't care. I don't mind the length from the side or projection so much as I do the vertical height from the front. I want it shortened & made softer (not so square and 'hard' looking). Should I be looking for a PS or maxillofacial? What result can I expect? I've seen pics of others and it seems like vertical reduction pushes their chin forward & gives a slight underbite. True?