In a bowl, mix together the flour, oats, baking soda and salt.
In another large bowl, add the butter and sugars and beat for about 1-2 minutes.
Add the eggs, vanilla extract and lemon juice and beat until well combined.
Slowly add the flour mixture and mix until a soft dough forms.
Gently fold in the chocolate chips and walnuts.
Make about 18 equal-sized balls from the mixture.
Grease the Air Fryer Basket with cooking spray and then slide inside.
Adjust the temperature of Air Fryer to 300 °F to preheat for 5 minutes.
After preheating, arrange half of dough balls into the greased Air Fryer Basket in a single layer.
With your fingers, press each dough ball slightly.
Slide the basket into Air Fryer and set the time for 7-8 minutes.
After cooking time is finished, let the cookies cool in the basket for about 1-2 minutes.
Then transfer the cookies onto a wire rack to cool completely before serving.
Repeat with remaining dough balls.