Set the air fryer to preheat at 375°F (190°C).
Combine olive oil, soy sauce, sweet chili sauce, rice vinegar, garlic powder, ground ginger, and honey in a bowl.
Season chicken breasts with salt and pepper then thoroughly coat them with the sauce mixture.
Arrange the chicken breasts in the air fryer basket and cook for 12-15 minutes, turning them once midway, until they reach 165°F (74°C) internally.
Meanwhile, toss Brussels sprouts with olive oil, salt, and pepper; add them to the air fryer basket and air fry for 8-10 minutes, shaking once halfway through, until crisp and golden.
Let the chicken rest for a few minutes after cooking before slicing.
Serve the sliced chicken alongside the crispy Brussels sprouts and drizzle any leftover sweet chili sauce over the top if you like.