Combine first 12 ingredients in a large zip-top plastic bag; add fish. Seal and marinate in refrigerator 30 minutes, turning once.
Remove fish from bag; discard marinade. Thread fish, green onions, and bell pepper alternately onto each of 4 (10-inch) skewers. Place on grill rack coated with cooking spray; grill 8 minutes or until desired degree of doneness, turning once.