In a small bowl, combine the miso paste, honey, soy sauce, mirin, sesame oil, and grated garlic. Mix until smooth.
Pat the salmon fillets dry with paper towels. If using skin-on salmon, lightly salt the skin side.
Flip the salmon so the skin side is down, then brush the miso glaze evenly over the top of each fillet.
Place the salmon skin side down in the air fryer basket.
Air fry at 400°F for 8–10 minutes, or until the salmon flakes easily and reaches your desired doneness.
Garnish with sliced green onions and sesame seeds before serving, if desired.