I think Bello is worth more in a trade, since he didn’t miss a season and also has a pretty favorable contract.
But for Boston, he’s easily replaced. His 1.9 fWAR in 166 IP seems bearable for Early, who was worth 1.1 fWAR in only 19 IP.
Trading Bello opens a spot in the rotation for the sought-after #2 starter, whatever that is. And with Tolle, Dobbins, Harrison, Perales and Fitts the Sox still have decent SP depth even before the season starts…