1. Preheat oven to 425°.
2. Combine 1 tablespoon sour cream, mayonnaise, 1 tablespoon lime juice, chipotle, sugar, vinegar, rind, 1/4 teaspoon salt, and pepper in a medium bowl, stirring with a whisk. Add coleslaw; toss to coat.
3. Combine remaining 2 tablespoons sour cream, remaining 1 tablespoon lime juice, remaining 1/8 teaspoon salt, milk, avocado, and garlic in a mini food processor; process until smooth.
4. Arrange frozen fish sticks in a single layer on a baking sheet coated with cooking spray. Bake at 425° for 27 minutes or until browned and crisp, turning once.
5. Heat tortillas according to package directions. Top each tortilla with about 1 tablespoon avocado mixture, 2 fish sticks, and 1/3 cup slaw mixture. Serve with lime wedges.