Heat the oven to 400°F (205°C). Line a large baking sheet with parchment or foil (set a wire rack on top if using).
Pat the wings very dry with paper towels. In a large bowl, toss wings with oil, salt, and pepper until evenly coated.
Arrange wings in a single layer on the baking sheet with space between pieces. Bake 25 minutes, then flip the wings.
Bake 20–25 minutes more, until wings are deeply golden and crisp and register at least 165°F (74°C) in the thickest part.
While the wings bake, make the glaze: in a medium saucepan whisk together orange juice, honey, soy sauce, rice vinegar, garlic, ginger, brown sugar, and red pepper flakes (if using). Bring to a boil, then reduce to a simmer for 8–10 minutes.
Stir cornstarch and water in a small bowl to make a slurry. Whisk into the simmering glaze and cook 2–3 minutes, until glossy and thick enough to coat a spoon. Remove from heat.
Transfer hot wings to a large bowl. Pour about half of the glaze over the wings and toss to coat.
Return wings to the baking sheet and bake 5 minutes to set and lightly caramelize the glaze.
Serve immediately. Brush or drizzle with remaining glaze as desired and garnish with orange zest, sesame seeds, and sliced green onions.