iI would not dismiss Hylexin completely, but it is rather expensive. The key ingredients are; Gynostemma Pentaphyllum extract (an obscure chinese herb, with latin and chinese name only), Hesperidine Methyl Chalcon (substanse found in lemon peel), Chrysin, peptides, and sunflower oil. The other ingredienst are mostly to make a smooth light cream, water, silicone etc. Ingredients are easily available online.
These ingredients are targeted to strengthen cappilaries and enhance the body's own "drainage" functions in the eye area. Darkeing of the eye area, caused by leaking capillaries and traces of red blood cells not yet fully "cleaned out" are to be treated by these ingredients. Different anti oxidants like vitamin C, green tea extract, witch hazel and caffein can also help with this trouble.
Darkeing of the eye area can also be caused by over production of pigments, more often in darker skinned people. Different ingredients can target this problem.