Sprinkle chicken with garlic powder, onion powder, and black pepper.
Soak rice noodles in a bowl with hot water until softened, about 10 minutes; drain and cut noodles in half with scissors.
Heat 1 1/2 tablespoons vegetable oil in a wok or large skillet over medium-high heat; cook and stir garlic in the hot oil until fragrant, about 1 minute. Add onion and green bell pepper; cook, stirring constantly, until onion and pepper are softened, about 5 minutes. Add remaining 1 1/2 tablespoons vegetable oil; cook and stir chicken into onion mixture until chicken is no longer pink in the center, 5 to 7 minutes.
Stir wine, soy sauce, and teriyaki sauce into chicken mixture; simmer until liquid is slightly reduced, about 3 minutes. Add baby corn and green onions; toss to evenly coat with sauce. Mix rice noodles into stir fry mixture; toss to coat. Cook and stir until heated through, about 2 more minutes.
