Preheat your air fryer to 400°F (200°C) to ensure a hot cooking environment.
Slice the russet potato into 1/2-inch thick wedges, then toss them in a bowl with 0.5 tbsp of avocado oil and a pinch of sea salt.
Place the potato wedges in the air fryer basket in a single layer and cook for 15-18 minutes, shaking halfway through until they are golden and tender.
While the potatoes cook, whisk together the flour, garlic powder, paprika, sea salt, and black pepper in a shallow dish.
Slowly pour the light beer into the flour mixture, whisking constantly until a smooth, thick batter forms.
Pat the cod fillets thoroughly dry with paper towels to ensure the batter clings to the surface.
Dip each cod fillet into the beer batter, coating all sides evenly and allowing any excess to drip back into the bowl.
Lightly grease the air fryer basket with the remaining avocado oil to prevent sticking.
Place the battered fish in the air fryer and cook at 400°F for 10-12 minutes, carefully flipping the fillets halfway through until the exterior is shattered-crisp.
Serve the hot fish and chips immediately with a fresh lemon wedge for a bright, acidic finish.