Season catfish fillets with seasoned salt. Mix orange juice, lemon juice, Dijon mustard, soy sauce, Worcestershire sauce, and hot sauce in a bowl.
Heat olive oil in large oven-safe skillet over medium-high heat; fry catfish in hot oil until lightly browned, 1 to 2 minutes per side. Spread mustard sauce on both sides of each fillet; drizzle remaining sauce over fish. Arrange bell pepper, onion, and garlic over fish.
Bake in preheated oven until fish is easily flaked with a fork, 15 to 20 minutes.
