>>7929822>>7930174I am neither of these posters but am just autistic/curious enough to look into this
There is no global rule about this; the closest thing is /h/ rule #1: “Information pertaining to the artist, character's name, originating manga/doujin, etc. is highly valued. Please provide this information if it is available to you.”
Not really a “rule” that is enforceable (without knowing a poster’s entire mental provenance of every image posted), more of a soft community aspiration.