In a large bowl, whisk together the flour, cornmeal, sugar, baking powder, and salt.
In a separate bowl, whisk the egg, buttermilk, and 1 tablespoon vegetable oil until smooth.
Pour the wet mixture into the dry ingredients and stir until a thick batter forms. Let it rest for about 5 minutes.
Meanwhile, preheat your air fryer to 375°F. Pour the batter into a tall glass to make dipping easier.
Insert a wooden skewer into each mini sausage, then dip it into the batter, coating it completely.
Place the coated corn dogs in the air fryer basket in a single layer, lightly spray with oil, and cook for 6–8 minutes, turning halfway, until golden brown and crispy.