In a large bowl, combine ground meat, egg, 1/2 teaspoon salt, 1/4 teaspoon garlic powder, 1/4 teaspoon dried oregano, 1/4 teaspoon dried rosemary, 1/4 teaspoon dried thyme, and black pepper. Use 2 tablespoons of the mixture to form each meatball. This should make around 16 total.
When the display panel on the cooker reads HOT, add the olive oil and the meatballs. Let the bottoms of the meatballs brown, about three minutes. Layer the squash/zucchini noodles on top of the meatballs, followed by the tomato sauce.
If your family prefers a smooth sauce, pulse the tomatoes, onions, and spices in a food processor or blender to the desired consistency before pouring it into the Instant Pot.