Its called fair use, as enforcer48 says, this is not a post who claims the art is made by the op, its an abuse report that under any concept of fair use can reasonably show both the plagiarized and the original artwork, what is being monetized here is not the art but the abuse report, the art is shown as supporting evidence.

Additionally, daio, yakubenko and any other art plagiarist that do not have permission to do derivative works of the original art cannot possibly claim copyright of the derivative work, that is only possible with the previous permission of the author, since they are in breach, they cannot claim rights to the derivative work, so nothing to worry about there, but thank you for your concern anyway.