In a medium mixing bowl, whisk together dark chili powder, smoked paprika, ground cumin, dried oregano, minced garlic, red pepper flakes, kosher salt, lime juice, and avocado oil. Add the shrimp, cover, and refrigerate for 20–30 minutes.

While the shrimp marinates, blend avocado, cilantro, jalapeño, minced garlic, lime juice, Greek yogurt, and salt in a food processor until smooth. Adjust with water as needed, and store in an airtight container.

Thinly slice green and purple cabbage, drizzle avocado crema over it, and toss gently. Set aside.

Heat a large skillet over medium-high heat. Add marinated shrimp in a single layer and cook for 4-6 minutes until curled and opaque.

Warm tortillas in a dry skillet. Layer each with cabbages slaw, shrimp, and drizzle with avocado crema. Garnish with cilantro and lime wedges if desired.