Air Fryer Meatballs

Name: Air Fryer Meatballs
Ingredients: 1 small yellow onion; 2 cloves garlic; 1/3 cup Italian-style fine breadcrumbs, or 1/3 cup plain, fine breadcrumbs mixed with 1 teaspoon Italian seasoning; 1 large egg; 1/2 bunch fresh basil or parsley, or a combination; 1 pound unseasoned meatloaf mix (ground beef, pork, and veal); 3 ounces Parmesan cheese, finely grated (about 3/4 cup store-bought or 1 1/2 cups grated on the small holes of a box grater); 4 ounces whole-milk ricotta cheese (1/2 cup); 1 teaspoon kosher salt; 1/2 teaspoon dried oregano; 1/2 teaspoon freshly ground black pepper; Cooking spray; 1 cup marinara sauce for dipping, or 1 (about 24-ounce) jar if serving under the meatballs (optional)