Frank Grillo had a couple of pretty great turns as Crossbones in Captain America: The Winter Solider and Captain America: Civil War, but it seems, or at least seemed, his days in the MCU were numbered.
In the comics, Crossbones was the one who killed Captain America following the events of Civil War.
Unfortunately, he was only in the cold open of Captain America: Civil War, as he appeared to die in an explosion.
In Captain America: The Winter Soldier, Frank Grillo’s character Brock Rumlow, who becomes Crossbones, essentially had a building fall on top of him.