Preheat the oven to 400°F (200°C). Line a rimmed baking sheet with parchment and drizzle or brush the surface lightly with oil so the meatballs don't stick.
In a large bowl, combine the ground pork, egg, panko, chopped green onions, minced garlic, soy sauce, sesame oil, salt, and pepper. Use your hands to gently fold until just combined—avoid overworking so the meatballs stay tender.
Portion the mixture into roughly 1 1/4-inch meatballs (about 24 meatballs). Roll each between your palms to form tight spheres, then place them evenly spaced on the prepared sheet.
Bake meatballs on the middle rack until browned and cooked through, about 15–18 minutes. Remove from oven and let rest on the pan for 5 minutes—this brief resting helps them firm up before glazing.
While the meatballs bake, make the glaze: combine honey, sriracha, soy sauce, rice vinegar, and grated ginger in a small bowl. Stir to blend. Mix the cornstarch with 1 tablespoon water to a smooth slurry and set aside.
Pour the glaze into a medium skillet and warm over medium heat. Once it begins to shimmer, stir in the cornstarch slurry and cook, stirring, until the sauce thickens and becomes glossy, about 1–2 minutes.
Add the baked meatballs to the skillet and gently toss to coat them in the glaze. Cook together for another 1–2 minutes so the sauce clings and the meatballs reheat through.
Transfer glazed meatballs to a serving platter and sprinkle with chopped cilantro or extra green onions and toasted sesame seeds, if using. Serve hot as an appetizer or over steamed rice for a full meal.