Preheat your air fryer to 400°F (200°C).
Wash the russet potato and slice it into thin, even wedges.
In a small bowl, toss the potato wedges with the avocado oil and a pinch of sea salt.
Place the wedges in the air fryer basket in a single layer and cook for 15-20 minutes, shaking halfway through, until they are golden and crispy.
While the chips cook, prepare the batter by whisking the egg white, light beer, flour, garlic powder, and paprika in a shallow dish until smooth and bubbly.
Pat the cod fillet completely dry with paper towels and season both sides with the remaining sea salt and black pepper.
Dip the cod into the beer batter, ensuring it is fully and evenly coated.
Once the chips are done, remove them and keep warm. Lightly grease the air fryer basket and place the battered fish inside.
Air fry the fish at 375°F (190°C) for 10-12 minutes, gently flipping halfway, until the crust is crunchy and the fish flakes easily with a fork.
Serve the crispy fish immediately alongside the hot potato wedges.