Preheat your air fryer to 400°F and slice the russet potato into thin, even wedges.
Toss the potato wedges in a bowl with half of the avocado oil, half of the sea salt, and the black pepper.
Place the wedges in the air fryer basket and cook for 15-20 minutes, shaking halfway through, until they are golden and crisp.
While the chips cook, pat the cod fillets completely dry with paper towels and season with garlic powder, paprika, and the remaining salt.
In a shallow bowl, whisk together the flour and light beer until a smooth, slightly bubbly batter forms.
Dip each cod fillet into the batter, allowing the excess to drip off, and lightly mist or brush with the remaining avocado oil.
Lower the air fryer temperature to 375°F, place the fish in the basket, and cook for 10-12 minutes until the coating is shattered-crisp and the fish flakes easily.