Line a baking sheet with parchment paper and set it aside.
Grab 3 bowls and set up a dredging station. Put the flour in the first bowl. Beat the eggs in the second bowl. In the third bowl, stir together the panko, Italian seasoning, salt, onion powder, garlic powder, and pepper.
Unwrap the string cheese. Dip the cheese first into the flour, then the egg, and then coat in the panko and set on the prepared baking sheet. After all 12 cheese sticks are coated, place the baking sheet in the freezer for at least 15 minutes.
After 15 minutes or when the coating is frozen, take the cheese sticks and dunk them in the egg once more, and then back into the panko for a second coating. Then place them back on the tray and freeze for another 30 minutes.
When you are ready to serve the mozzarella sticks, remove them from the freezer and preheat your air fryer to 400 degrees F.
Spray the air fryer basket with olive oil spray and place the sticks into the basket in one even layer. Spray the cheese sticks with olive oil spray.
Cook in the air fryer for 3 minutes. Check the cheese sticks, flipping and shaking them. Then cook for another 3-4 minutes. The mozzarella sticks are finished when they are golden brown and crispy. Serve warm with marinara for dipping.