Whisk together water and cornstarch in a small pan until no lumps remain. Over medium heat add 3/4 cups granulated sugar, 3/4 teaspoon cinnamon, nutmeg vanilla, lemon juice and salt to the cornstarch mixture. Cook for two minutes, stirring occasionally; mixture will begin to thicken. Add apples and turn down the heat to low for 7-12 minutes or until the apples are soft. Remove from heat.
Place one tablespoon of caramel sauce on each warm tortilla and top with 1/2 cup of the apple mixture.
Tuck the ends and roll the tortilla to create a chimichanga. Secure with a toothpick if needed.
Spray air fryer basket with cooking spray and place two rolled chimichangas, seam side down, in the basket. Air fry for seven minutes.
Combine brown sugar and remaining granulated sugar in a shallow bowl.
Remove cooked chimichangas from basket and roll in cinnamon-sugar mixture. Top with vanilla ice cream and a drizzle of caramel sauce if desired.