Combine shredded green cabbage, purple cabbage, and grated carrot in a large bowl. Whisk together the mayonnaise, apple cider vinegar, honey, and lime juice in a small bowl, pour over the cabbage, toss to coat evenly, season with salt and pepper, fold in cilantro if using, then cover and refrigerate while you prepare the shrimp.
Pat the shrimp completely dry with paper towels, then toss in a bowl with the olive oil, lime juice, smoked paprika, garlic powder, cumin, chili powder, cayenne (if using), salt, and pepper until every piece is evenly coated. Let sit for 5 minutes while the grill heats up.
Preheat an outdoor grill or cast iron grill pan to medium-high heat (400–425°F / 200–220°C) and lightly oil the grates or pan surface. The grill is ready when a drop of water evaporates immediately on contact.
Thread 3–4 shrimp onto each skewer, piercing through both the thick end and the tail so they lie flat, with no overlapping. If using wooden skewers, ensure they have been soaked in water for at least 30 minutes.
Grill the shrimp in a single layer for 2–3 minutes on the first side until pink with visible sear marks, then flip and grill for 1–2 minutes more until opaque and curled into a loose C-shape. Remove immediately from the grill to avoid overcooking.
Heat corn tortillas one at a time in a dry skillet or comal over medium-high heat for about 30 seconds per side until lightly charred and pliable, then keep them wrapped in a clean kitchen towel to stay warm and soft.
Stack two warm tortillas per taco, top with a generous spoonful of cabbage slaw, 3–4 grilled shrimp, and a few avocado slices, then drizzle with hot sauce or chipotle crema and finish with fresh cilantro, jalapeño slices, and a squeeze of lime.