I am looking for a non-surgical solution to smooth out the chin area below the mental crease? (Photos)

Botox only lasts 4 to 6 months. That means getting maintenance retreatment at least twice a year. The hyaluronic acid filler will last for about a year. Understand that there is fundamentally nothing wrong with your chin and the only real reason to treat your chin is that you are asking for service. The big risk with botox is that treatment of the mentalis muscle can easily be out of balance. That causes disturbing wading of the chin. For that reason and the treatment time frame, I generally prefer to use Restylane or Lyft for chin treatment. 

You will probably get the best result by using a combination of Botox and a small amount of filler.  The two products can lessen the prominence of the chin area.  See an experienced injector in your area for a consultation.