I haven't seen it discussed, but what about Turner's defense? Does he need to move to 2B or 3B? That changes a lot of potential trade scenarios.
Moving Schwarber out of the leadoff spot is the first move I make.
Castellanos, Schwarber and Realmuto are the only $20 million contracts I could see them trading. Of those 3, I'd keep Schwarber and put him in the cleanup spot.
Castellanos has 2-years remaining. Baltimore potentially could lose Sontander, the Red Sox could lose O'Neill and the Dodgers could lose Hernandez and don't forget the Yanks will keep one of Soto and Verdugo. That is 4 potential landing spots for Casty. CFer - Rojas is the next Jackie Bradley Jr. which works if your left and right fielder can rake.
San Franciso or San Diego could possibly be interested in Realmuto.