How do I make my jaw look more symmetrical and reduce fat under my jaw? My research hasn't shown any clear-cut options. (photo)

You have a very narrow jaw/chin from the front and on your profile view it looks as though your have a pretty undefined angle of mandible region.  I agree your chin doesn't need to project more forward at all on your profile, which is the usual situation when someone gets a chin implant.  I think you have a couple options.  You could get filler injections at the angle of your jaw and on your right chin (where it is higher) to give you a more defined and symmetric jaw.  If you liked the look of this, you could have surgery with off the shelf mandibular angle implants and a small custom implant for the chin just to correct the subtle asymmetry.  The cadillac therapy would be a custom mandibular implant based on a CT scan of your mandible which would allow you to customize where and how much augmentation is provided. This is a big surgery and quite expensive but would provide probably the most pleasing result.  I think it is wise to start with filler to see what volume in different locations can achieve for you...it is relatively inexpensive, reversible, and lasts 1-2 years. Best of luck!

Your (half face covering) frontal view photograph gives limited information., so the answer may be insufficient to fulfill your question. Usually, the reason for asymmetry is very complicated and there are combined asymmetry of bony skeleton and soft tissues. Due to limited information, we cannot tell which part plays major role in your case. Taking X-ray, and CT scan may give us to analyse furthermore. Thank you.

You actually have several options for your chin and jaw problems. One of the most obvious is a chin surgery, which can help you achieve a more sculpted jawline and a harmonious balance to your facial features.
You may also try facial liposuction on your chin, as it removes the excess fat that has accumulated under your chin, thereby reshaping and contouring your face.
Another option is a lower facelift, which can enhance the appearance of your jaw.
Each of these procedures has its own sets of pros, cons, and qualifications. Consult a reputable board-certified surgeon for a proper assessment to know which treatment will best suit your needs. Best wishes.

You have a longer face development pattern and that results in  'narrow' face. The chin becomes the 'point' of the "V" and is accentuated. To achieve a natural balanced appearance, you would augment the back and front of the jaw. This would include the angle, the body/midsection, and the chin. Improving the symmetry and defining the jawline to balance the midface. The area alongside the nose/upper lip is shallow due to the growth pattern so you have to avoid a 'too strong' lower jaw as well. This is common surgery for some of us.