01 - Combine green and red cabbage, carrot, and cilantro in a large bowl. Whisk together mayonnaise, lime juice, salt, and pepper in a small bowl. Pour dressing over vegetables and toss well. Refrigerate until ready to use.
02 - Mix sour cream, mayonnaise, lime juice, garlic powder, and salt in a small bowl until smooth. Set aside.
03 - Pat fish fillets dry with paper towels. Whisk flour, baking powder, salt, pepper, and paprika in a medium bowl. Beat egg with sparkling water in another bowl. Pour wet ingredients into dry and whisk until just combined.
04 - Heat about 1 inch of vegetable oil in a deep skillet over medium-high heat to 350°F. Dip fish strips into batter, letting excess drip off, then carefully lower into hot oil. Fry in batches for 3 to 4 minutes, turning once, until golden and crispy. Drain on paper towels.
05 - Place crispy fish in warmed tortillas. Top with cabbage slaw and drizzle with crema. Garnish with fresh cilantro and serve with lime wedges.