Preheat the air fryer to 390°F for 3 minutes. If your basket is small, plan to cook the chicken in two batches so the pieces can crisp instead of steam.

In a small bowl, whisk together the soy sauce, hoisin sauce, rice vinegar, honey, sesame oil, ginger, garlic, optional chili-garlic sauce, and the white parts of the scallions. Set the ginger-scallion sauce near the air fryer.

Toss the broccoli and bell pepper with 1 teaspoon neutral oil and 1/4 teaspoon kosher salt. Air fry at 390°F for 6 to 8 minutes, shaking once, until the broccoli edges are lightly browned but still bright. Transfer the vegetables to a large bowl.

Pat the chicken pieces dry. Toss them with the cornstarch, remaining 2 teaspoons neutral oil, remaining 1/2 teaspoon kosher salt, and black pepper until evenly coated.

Air fry the chicken at 390°F for 10 to 12 minutes, shaking halfway, until the pieces are golden at the edges and reach 165°F on an instant-read thermometer. If working in batches, make sure each batch reaches 165°F, then transfer the cooked chicken to the bowl with the vegetables while the next batch cooks.

Return all chicken and vegetables to the air fryer basket. Drizzle with about two-thirds of the ginger-scallion sauce and toss with tongs to coat. Air fry at 370°F for 2 to 3 minutes, just until the sauce turns glossy and clings to the chicken.

Divide the cooked rice among 4 bowls. Top with the glazed chicken and vegetables, then spoon over the remaining sauce to taste.

Finish with the green parts of the scallions and toasted sesame seeds, if using. Serve immediately while the chicken edges are still crisp.