Marinate shrimp. Whisk together oat milk, vinegar, kosher salt, garlic powder, onion powder, and black pepper then pour over peeled and deviled shrimp and stir to coat. Set aside.
Make sauce. Add all the sauce ingredients to a blender or food processor and blend until completely smooth, scraping down the sides as needed.
Make slaw. In a medium bowl, combine the green cabbage and carrot. Toss with a couple tablespoons of the sauce. Set aside.
Dredge. Add the potato starch to a shallow bowl. One by one, remove the shrimp from the marinade, letting excess drip off. Dip both sides fully in the starch, tapping off the excess. Transfer breaded shrimp to a plate.
Cook the shrimp. Heat a high walled large skillet over medium heat with enough oil to cover the bottom of the pan. Cook the shrimp in a single layer for a few minutes on each side, depending on their size until golden brown and crispy. Transfer to a wire rack and continue with the process until you've cooked all the shrimp.
Assemble. Add slaw to the bottom of a warm tortilla, followed by crispy shrimp and a drizzle of the creamy sauce. Serve with lime wedges if desired.