There is one thing I can definitely guarantee you - Quickseller is not going to go after you criminally or civilly.

"Your honor, I'm on this Bitcoin forum (oh, you mean that darknet anonymous serial killer drug dealer fake money?) and I buy and sell member accounts so people can impersonate and scam people, and/or promote illegal gambling websites. Well, some user tried to get back the $5 account that was hacked and sold to me! Put the original user in jail!"