Yes, Botox can absolutely be used for jawline contouring or face slimming.
Botox Masseter Jaw Reduction - Benefits, Costs & Results
Aesthetics HawaiiV-Line Jaw Slimming using Kybella™ and Masseter
Face Slimming Botox, Botox for Facial Slimming - Dr. Michele Green
Achieve the Perfect V-Line: Non-Surgical Facial Contouring with
CAN BOTOX BE USED FOR FACE SLIMMING & JAW CONTOURING?
Facial Slimming Injections & Treatments Sydney
Masseter Botox: Everything You Need to Know About the Treatment in
Injectable Stress Relief: Masseter Botox — Dr Ed Robinson Aesthetics
Jaw Reduction & Calf Slimming with Fillers: Botox, Dysport, Xeomin