Start by preheating your air fryer to 350°F (175°C). In a large mixing bowl, combine the flour, baking powder, baking soda, salt, and sugar. Whisk them together until well blended.
In a separate bowl, whisk the egg and then mix in the cottage cheese, vanilla extract, and melted coconut oil until smooth.
Pour the wet mixture into the bowl with dry ingredients. Gently combine them using a spatula, being careful not to overmix. Just before everything is fully incorporated, fold in the blueberries.
Scoop tablespoon-sized amounts of the batter and place them in a lightly greased air fryer basket, leaving room between them for expansion.
Air fry for about 8 to 10 minutes, until the doughnut holes turn a golden-brown color and are cooked through. Allow them to cool slightly before removing from the basket.
While still warm, dust the donut holes generously with powdered sugar for a delightful finishing touch.