Should I do this trade?

Your WRs are very weak for a 10 team league, but this may not be the way to upgrade them. Why would you take on the risk of Favre when you've got a solid QB with Brady? I ume you have really good RBs (at least I hope so) and I'd try to upgrade at WR by taking a downgrade at QB or RB in a combo deal. It's hard to say without seeing your whole roster.