Preheat air fryer to 375°F.
Slice the sweet onion into 1/2-inch thick rings and separate them.
In a medium bowl, whisk together the chickpea flour, garlic powder, smoked paprika, sea salt, and black pepper.
In a separate bowl, beat the egg whites until frothy, then gently fold in the light beer.
Gradually whisk the dry ingredients into the egg white mixture until a thick, smooth batter forms.
Dip each onion ring into the batter, ensuring it is fully coated, and let any excess drip off.
Place the rings in a single layer in the air fryer basket and lightly spray with avocado oil.
Air fry for 10-12 minutes, flipping halfway through, until the coating is golden and crisp.
While the rings cook, stir together the Greek yogurt and minced chipotle in adobo to create the aioli.
Serve the warm onion rings immediately with the smoky chipotle dipping sauce.