Combine 2 teaspoons sugar, chili powder, chile powders, and 1/4 teaspoon salt in a shallow dish. Add shrimp to spice mixture; toss well to coat.
Heat 1 tablespoon oil in a large nonstick skillet over medium-high heat. Add 1/2 cup onion, bell pepper, garlic, and ginger to pan; sauté 3 minutes. Add remaining 1 1/2 teaspoons sugar and corn to pan; cook 3 minutes, stirring occasionally. Stir in vinegar; cook 30 seconds. Transfer corn mixture to a bowl; stir in remaining 1/4 teaspoon salt and 1/2 cup green onions.
Wipe pan with a paper towel. Heat remaining 2 teaspoons oil in pan over medium-high heat. Add shrimp to pan; sauté 3 minutes or until done, turning once. Serve with corn mixture.