In a medium bowl, combine the low-sodium soy sauce, honey, rice vinegar, sesame oil, minced garlic, and grated ginger. Whisk these ingredients together until well blended.
Place the chicken thighs in a resealable plastic bag or a shallow dish. Pour the marinade over the chicken, ensuring each thigh is well-coated. Seal the bag or cover the dish with plastic wrap and refrigerate for a minimum of 30 minutes, or up to 2 hours.
Once marinated, remove the chicken thighs from the marinade, shaking off any excess liquid. Keep the marinade set aside for later use.
Set your air fryer to preheat at 375°F (190°C).
Arrange the chicken thighs in the air fryer basket skin-side down in a single layer. Cook for 10 minutes.
While the chicken cooks, take the reserved marinade and pour it into a small saucepan. Bring it to a gentle boil over medium heat, then lower the heat to allow it to simmer for about 5 minutes. In a small bowl, mix together the cornstarch and water to create a slurry, and stir this into the simmering marinade. Continue cooking until the sauce thickens, then remove from heat.
After the initial 10 minutes, carefully flip the chicken thighs so they are skin-side up. Brush them generously with some of the thickened marinade. Cook for an additional 10-12 minutes, or until the chicken's internal temperature reaches 165°F (75°C).
Once fully cooked, remove the chicken thighs from the air fryer and let them rest for about 5 minutes.
To serve, drizzle the remaining thickened marinade over the chicken thighs. Garnish with a sprinkle of sesame seeds and sliced green onions.
Notes
For best flavor, marinate the chicken for up to 2 hours.