Preheat the oven to 425 degrees F (220 degrees C). Line a rimmed baking sheet with foil.

Mix together chili powder, paprika, cumin, onion powder, salt, and pepper for tacos in a small bowl until well combined.

Brush 2 tablespoons oil all over the prepared pan, then add mahi mahi fillets. Drizzle remaining 1 tablespoon oil over the fillets and rub to coat. Sprinkle spice mixture evenly over both sides of the fillets.

Bake in the preheated oven until fish flakes evenly with a fork and drippings are caramelized, 10 to 12 minutes.

While the fish is baking, prepare slaw by combining coleslaw mix, cilantro, jalapeno pepper, oil, lime juice, vinegar, garlic powder, salt, and pepper in a bowl; toss until well combined.

Stir together sour cream, chipotle in adobo, adobo sauce, and salt for crema together in a small bowl.

Char tortillas over a gas flame.

Remove fish from the oven and flake it with a fork.

Fill tortillas with fish and slaw. Drizzle with crema and squeeze lime wedges over top.