I don't think this is possible under posting rules. The winning bidders needs to sign the player. Once the players signed, he can be traded, but that probably needs to wait until after May of the following season to happen, like other free agent signings. According to today's USA Today, back in 1997, the Padres reached an agreement with the Chiba Lotte Marines, and then traded the rights to Hideki Irabu to the Yankees.