I see that characters have tags like "tanned" or "green skin" but on https://www.animecharactersdatabase.com/advancedsearch.php there's no option for chose the color of the skin.
Is possible add this option?

How about this as a solution :

I've added a visual trait filter option to tags.

私は日本語を少し読むと書くをできます。あなたも？