I stared at your face a long time, took a break and looked at it again.
I do not find that your face is "a long face". In fact, your face is quite attractive as is. Leave it alone.
Thank you for your picture. In my opinion, your face does not appear long. You may have some mild asymmetry to your chin that can be corrected with a sliding genioplasty. If your chin was shortened then your lower facial third would be out of balance. Please visit with several board certified plastic surgeons for a consultation. Best wishes.
There are two fundamental techniques to aesthetically reduce the long face. Vertical reduction of the chin through an intraoral wedge removal is the one bony removal method and it does actually create true facial shortening The other method is to widen the face through lateral cheek augmentation. This is an illusionary technique that is often done in combiantion with vertical chin reduction to create a more profound shortening appearance if desired.
One can reduceb the chin height OR lengthen The ramus/ back of jawline. Not an umcommon issue but readily changed.