Preheat the oven to 400°F (200°C) and line a rimmed baking sheet with parchment paper.
In a large bowl, toss the sweet potato slices with 1 tablespoon of olive oil, sea salt, and black pepper until thoroughly coated.
Arrange the sweet potato slices in a single layer on the baking sheet and bake for 20 to 25 minutes, flipping once at the 12-minute mark, until edges are golden and crisp.
While the potatoes are baking, pat the fish fillets dry with paper towels and apply the Cajun seasoning evenly to both sides, pressing slightly to adhere.
Heat the remaining 1 tablespoon of olive oil in a non-stick or cast-iron skillet over medium-high heat.
Place the seasoned fish fillets in the skillet and sear for 3 to 4 minutes per side, or until the internal temperature reaches 145°F (63°C) and the flesh flakes easily with a fork.
Remove the sweet potato chips from the oven and the fish from the skillet.
Plate the fish alongside a serving of sweet potato chips, garnished with fresh parsley and lemon wedges.