The Yankees and Mets rarely get together as swap partners. In 2001, the Yankees sent David Justice to the Mets in exchange for Robin Ventura. And in 2004, Mike Stanton came over to the Bronx, and Felix Heredia moved to Queens. But generally speaking, deals between the two teams are not anything to write home about.
In 2017, however, each team is on a divergent path from the other, and each may have what the other is looking for.
Whether or not they are inclined to admit it, the Mets could mail in the rest of the season, and no one would notice the difference given the way they have been playing.