In a large mixing bowl, combine the 1 box yellow cake mix, 2 large eggs, and 1/3 cup applesauce until combined.
Add the diced 1/2 cup apples1/2 teaspoon ground cinnamon, 1/8 teaspoon ground nutmeg 1/2 teaspoon pure vanilla extract, and 2 tablespoons brown sugar a small saucepan and saute over medium heat for 3-4 minutes until the apples have softened
Allow the apple mixture to cool slightly and stir into the cake batter mix.
Fill the whoopie pie cavities using a whoopie pie pan or drop tablespoons of the batter onto parchment paper. You’ll be working in batches.
Set the air fry setting to air fryer temperature of 320 degrees and set cook time for 5-6 minutes or until the whoopie pies are cooked through.
Cool the whoopie pie cakes on a wire rack. Meanwhile, prepare the filling.
In a large mixing bowl add the 8 ounce cream cheese, 4 tablespoon butter, 1/2 cup powdered sugar, 1 teaspoon ground cinnamon, 1 teaspoon pure vanilla extract and cream until smooth with an electric or stand mixer.
Fill a piping bag with the cream filling and pipe onto one cake, and top with another to create a whoopie pie.