Combine 1 cup salsa and 4 tablespoons lime juice In small bowl. Place swordfish steaks in large shallow glass baking dish. Pour salsa mixture over steaks. Cover swordfish; let marinate at room temperature 15 minutes.
Prepare grill. Combine black beans, corn, remaining 1 cup salsa and remaining 2 tablespoons lime juice in medium-size saucepan. Warm over medium-low heat.
Grill swordfish 4 minutes on each side or until fish flakes easily with fork. Remove bean mixture from heat; stir in scallions. Serve with fish.