I can check the information of the club which brought my player by clicking the club name as shown in the News thread. Pls note that this thread only exists for 2 days. So, if you want to check later, you should add the buyer as your friend, or add your ex-player as favorite. As I remember, player statistics are not available.

Club which sold any player to my club can also be checked in the same way, unless the club is not a true club.