Would Botox in the chin help me achieve a more balanced look? (photo)

It's a little difficult to give specific recommendations for your chin without more pictures and an in-person physical examination. Botox/neurotoxins wouldn't do much for this situation.

Given that you are concerned with it being protruded or rounded, I'd be hesitant to recommend fillers unless your side profile appears retruded/set back. Fillers along the jowl region would square off the jaw, taking away some of the rounded appearance, but masculinizing the appearance which may not be desirable.

If you have a lot of bony excess, a surgical procedure to shave off some of that may be warranted. If there are other skeletal or dental issues, you may require the assistance of a maxillofacial surgeon to avoid issues with dentition when undergoing a setback of the jaw.

Hi! I would consider trying some botox to your chin/mentalis muscle to see if that helps you achieve what you are looking for. It is hard to give a full assessment without side photos or dynamic photos and also not knowing exactly what you are bothered by but since botox is temporary, you could always try it out.