In a small bowl, whisk together soy sauce, honey, 1 tablespoon water, rice vinegar, grated ginger, and minced garlic to make the teriyaki sauce base.
Pour half of the teriyaki sauce into a shallow dish and place the salmon fillets skin side down. Marinate for 5 minutes.
Preheat the air fryer to 400°F (200°C) for 3 minutes.
Remove the salmon from the marinade and place the fillets skin side down in the air fryer basket. Reserve the marinade.
Air fry the salmon for 10 minutes or until the internal temperature reaches 145°F (63°C) and the salmon flakes easily with a fork.
While the salmon cooks, pour the reserved marinade into a small saucepan and bring to a gentle boil over medium heat.
In a small bowl, mix cornstarch with 1 tablespoon cold water until smooth. Slowly whisk the cornstarch slurry into the boiling marinade.
Cook and stir the sauce for 1-2 minutes until thickened. Remove from heat and stir in sesame oil.
Once the salmon is cooked, transfer to serving plates and brush generously with the thickened teriyaki sauce.
Garnish with toasted sesame seeds and sliced green onions before serving.