What can I consider to improve the look and symmetry of my upper eyelids? (Photo)

Thank you for your question and photo. Since you don’t appear to have excess skin or prominent signs of aging around your eyes, you may benefit most from hyaluronic acid dermal fillers to make your eyes appear more symmetrical.
This injectable treatment option can add volume to specific areas of the face to create a balanced appearance, with results lasting up to a year or more. I recommend scheduling an in-person consultation with an experienced, board-certified injector who can conduct an in-person examination and suggest the best treatment option for you.

As we age, our eyelids naturally sag and droop. A combination approach would be best to see visible improvement. In terms of non-surgical treatment options, I would recommend a Chemical Brow Lift (using Botox, Dysport, Xeomin, or Jeuveau) and filler injections to rejuvenate the temples, eyebrow, eyelid, eye troughs, upper eye hollows, and forehead. I typically combine this with Ultherapy and thread lifting to lift the brow; RF and skin tightening laser treatments to stimulate collagen production and rejuvenate the skin; and laser or superficial RF devices for improvements in texture, color, and any crepey skin around the eyes as needed. In some cases, surgery is the best solution to achieve the desired results. See an expert for a formal consultation. Best, Dr. Emer.​

Eyelid asymmetry is fairly common and may be due to eyelid ptosis. With ptosis, the eyelid skin sits lower on the pupil and the eyebrow raises to compensate. Ptosis can be congenital, traumatic, and acquired. There are several different surgeries to correct the eyelid ptosis.
Additionally hollow eyes can be improved for fat grafting and "off-label" fillers.

Although you are exhibiting no ptosis (lid droop) in the photo, you most certainly have it with your left eye compensating significantly using both the levator and the frontalis muscles. The levator is detached from its normal position explaining the increased tarsal show. You need to be evaluated by a plastic or ophthalmic plastic surgeon who is an expert in ptosis correction. (Though the example is not exactly the same, see the last example in the attached link.)