Asymmetry is common
Most people are asymmetrical for various reasons, and in many women cellulite, water retention and deep fat levels are worse on one leg than the other. Usually the right side is worse in most women.
The explanation is simple: most people tend to stand putting more pressure on one leg or cross their legs, compressing one leg more than the other.
As a result, venous return and lymphatic drainage is hindered on that leg, which means reduced removal of water, waste products and fatty acids from the fat tissues of that specific leg. This leads to more cellulite, water retention and fat.
To make matters worse, fat can still enter the fat tissues, as arterial flow is much stronger than venous return and lymph drainage.
Any other cause of poor lymphatic or venous function on one leg, apart from compressing the leg by crossing it or by putting pressure on it while standing, can also lead to more pronounced cellulite on that leg.
The solution to this problem is simple:
Prevent cellulite by being very active and by not supporting yourself on one specific side / crossing your legs. And have a course of intensive cellulite treatments, with most of the treatment time spent on the more affected leg than the other.
Cellulite creams act more slowly (but then again they are more economical than treatments), so it does not make sense to apply just on the "worse" leg. So use of a concentrated cellulite cream on both legs, and when you are happy with the results on the "good" leg, continue with applying the cream only on the more affected leg.