Are there any beauty products to care for old pigmentation?

It has been in this state ever since I got a wound near my scalp and a scab formed quite a long time ago. I would like recommendations for products that are good for hyperpigmentation. Are there any ingredients or recommended products that would be effective even on this old pigmentation if used consistently? I do not want recommendations for anything that stings or is irritating.

Up until now, I have made sure to apply whatever was recommended whenever I remembered, typically lemon or Vitamin C products. However, these products are quite irritating, so I would stop using them altogether after applying them once or twice, which has always been a dilemma. I was wondering if asking about finding the right products on a beauty community would be a good idea, so I am asking here.

Please recommend an effective pigmentation care product that I can use consistently.