In a small bowl, mix smoked paprika, cumin, garlic powder, oregano, cayenne, and salt. Pat shrimp dry and toss with the spice mixture until evenly coated.
Heat olive oil in a large skillet over medium-high heat. Add shrimp in a single layer and cook for 1–2 minutes per side, until opaque and slightly charred. Remove from heat.
While shrimp cooks, make the avocado crema: In a blender or small food processor, combine avocado, sour cream, lime juice, jalapeño, garlic, and cilantro. Blend until smooth, adding a tablespoon of water if needed to thin. Season with salt to taste.
Warm tortillas in a dry skillet or microwave until pliable.
To assemble, spread a spoonful of avocado crema on each tortilla. Top with a few shrimp, some shredded cabbage if using, and a sprinkle of cilantro. Serve with lime wedges.