Should I accept this Trade?

I wouldn't go for it. In my opinion, Mark Teixeira is slightly overrated. His batting average is .243, and his BABIP (.214) is far worse than his previous career low. The only upsides to him are homers and RBIs, which are good upsides, but I think they come too sparsely to be worth trading away CC Sabathia, who has been dominant as of late and is a great fantasy pitcher anyways. If only because of the wins, CC is one of the best pitchers to have in an H2H points league. He is projected to finish at 21-8, which is great for fantasy baseball. So no, you shouldn't accept the trade. If you really want a power hitting first baseman, there are a LOT of other options (like Pujols, Fielder, Adrian Gonzalez, Miguel Cabrera, etc.) I'm sure you can make some sort of trade involving a great starting pitcher for one of those (I would personally recommend Gonzalez if you can get him)