What is the ruling on selling "cosplay" clothing and its accessories, which are costumes of TV or cartoon characters (especially Japanese ones), even if they do not bear images of animate beings, and make the wearer look like the character, such as "Detective Conan"?

There is no Shari'ah impediment to selling cartoon clothes and similar items like glasses, so long as they are free of images of living beings and symbols indicative of corrupt beliefs, such as the cross. Also, as long as the cartoon does not symbolize customs specific to disbelievers, otherwise, anything that promotes such customs would be prohibited. Otherwise, their ruling is the same as clothes imported from disbelievers' lands, and the basic principle regarding them is permissibility.