Beat the softened cream cheese, 1/3 cup granulated sugar, and vanilla extract until smooth. Stir in the fresh blueberries gently, along with the optional lemon juice or lemon zest, taking care not to crush the berries.

Place about 2–3 tablespoons of cheesecake filling in the center of each flour tortilla. Fold the sides inward, then roll tightly from the bottom to form a sealed burrito-style chimichanga, placing each one seam-side down.

Brush the outside of each filled tortilla lightly with melted butter or coat it with cooking spray. Secure any loose tortilla edges with a toothpick if needed, remembering to remove toothpicks before serving.

Arrange the chimichangas in the air fryer basket with space between them for air circulation. Air-fry at 350°F for approximately 5–8 minutes, turning halfway if needed, until lightly golden and crisp.

Combine the remaining 1/4 cup granulated sugar with the cinnamon in a shallow bowl. Brush or lightly coat the hot chimichangas with the cinnamon sugar, then serve warm with powdered sugar or blueberry sauce if desired.