Combine first 6 ingredients in a large bowl. Whisk in beer.
Pour oil to a depth of 2 inches in a deep saucepan or Dutch oven. Heat over medium-high heat until temperature reaches 350°.
Cut fish into bite-size pieces; dip into beer batter, letting excess batter drip back into bowl. Fry, in batches, 2 to 3 minutes or until golden brown and crispy on all sides. Drain on paper towels. Sprinkle with additional salt, if desired.
Heat tortillas according to package directions. Divide fish among tortillas, using 2 stacked tortillas for each taco. Top with cabbage, cilantro, tomatoes, and Chipotle Crema. Serve with lime wedges.