Early 40s, would a minilift help soften my NL fold and help my jowls? Also, should I get a FL on just my left side?

Thank you for your question and sharing your photographs.
The only time when the unilateral facelift can be of value is in the presence of a facial palsy that has not recovered.
The surgical intervention does not produce a level of precision in the left that can be tailored to match the opposite side.
More importantly though my impression is that on the left side the nasolabial fold is deeper but at the same time the corner of the mouth is slightly higher and the chin is slightly deviated to the left also. In aggregate, the effect is of a different contour on the left hand side, which leads to the impression that the ageing process is affected differently.
The elasticity of your skin is very good and therefore this nonsurgical treatments are also a reasonable option.
For the surgical alternatives, deep plane facelift or minimal access facelift procedure carried out on both sides is likely to be the better solution. Neither will produce perfect symmetry but they can produce a softening of the facial features. The majority of the impact will be redistribution of the volume rather than volume loss the fact that the volume in the jawline region diminishes and the volume in the cheekbone area increases has a tendency to highlight the appearance of the eyes and in general is a positive type of change. This
To understand the potential impact of the deep plane facelift intervention I would suggest that you lie down completely flat and have a look in the mirror. The tension changes in the soft tissues generate contour changes that are relatively similar to the impact of a deep plane facelift procedure. If you feel that they correspond to your aspirations and that the level of symmetry is adequate, it would be worth discussing with provider that offers this type of intervention.

A mini facelift will lift your cheeks and correct your jowl fullness. I would not recommend doing it only on one side for symmetry issues.

Thank you for providing additional pictures and clarifying your concerns. It's not unusual for facial aging to occur asymmetrically, leading to differences in appearance between the two sides of the face. Your observation about the age disparity between the left and right sides of your face is insightful and helps in formulating a targeted approach.

Before considering surgical options, it's worthwhile to explore non-surgical treatments that can address skin laxity and volume loss, particularly on your left side. One such option is Thermage, a non-invasive treatment that uses radiofrequency technology to tighten skin and stimulate collagen production. This could potentially help in achieving a more youthful appearance on the left side of your face without the need for surgery.

Additionally, considering that your left side appears to have less soft tissue volume and smaller facial bone structure, Sculptra injections could be beneficial. Sculptra, a poly-L-lactic acid filler, works by stimulating your body's own collagen production, gradually improving facial volume. This can create a more balanced and youthful appearance.

While a one-sided facelift is rarely performed due to concerns about asymmetry, it remains a potential option if non-surgical treatments do not yield satisfactory results. However, it's crucial to proceed with caution, as facelifts involve more risks and a longer recovery period compared to non-surgical procedures.

I recommend scheduling a consultation with a board certified plastic surgeon to thoroughly assess your facial structure and skin condition. You will be able to discuss all possible options and decide on the most suitable treatment plan that aligns with your aesthetic goals and minimizes potential risks.