For JP creators, they take the copyright stuff VERY seriously. They don't have anything like fair use so anytime you wish to use/share/transform someone's work, the party MUST ask for permission. This is a cultural thing in Japan and every entity that operates there complies by this. Stuff like doujinshi or fan created works that uses someone's IP in Japan is a gray area that directly contradicts this but realizes that there is a demand for this so people would do these type of stuff with the implication that if asked to stop/purge these works, they instantly comply (I.E. Hololive MMD works from the bigger fanmade users). Of course there is some that operates knowingly not giving a shit about copyright because god forbid you can't stop the gooning but there has been known incident of people getting fined by selling stuff you didn't get permission to the rights to like this incident
here. You can take these ramblings of an old man for someone who stayed in Japan for like 1 1/2 year with a grain of salt if you wish.