Combine green onions, juices, soy sauce, brown sugar, vinegar, and ginger in a small bowl.
Combine five-spice powder, salt, and pepper. Sprinkle both sides of fish evenly with spice mixture.
Heat oil in a large nonstick skillet over medium-high heat. Add fish to pan; cook 2 minutes on each side or until fish flakes easily when tested with a fork or until desired degree of doneness. Remove from skillet, and serve with sauce.