In a large plastic zipper bag, combine the olive oil, vinegar, Worcestershire sauce, Dijon mustard, garlic, onion, salt, and pepper. Shake to combine.

Add the steaks to the bag, press out the air, seal the zipper, and massage the marinade around the steaks gently. Marinate in the refrigerator for at least 1 hour, up to 12 hours.

Preheat the air fryer to 400 degrees F for 5 minutes. 

Remove the cube steaks from the marinade, allowing excess liquid to drip off the meat. Spray the inner basket with cooking oil spray and place the steaks in a single layer in the basket, working in batches as needed.

Air fry for 4-6 minutes, depending on thickness, or until the steaks have reached an internal temperature of 145 degrees F. Be sure not to overcook as the steak will get tough.

Rest for 5 minutes before slicing and serving.