Pat the fish dry with paper towels.
In a bowl, combine olive oil, chili powder, cumin, smoked paprika, garlic powder, kosher salt, black pepper, lime zest, and lime juice; toss fish to coat and let sit about 10 minutes.
Make the slaw: Combine cabbage and cilantro; whisk lime juice, olive oil, honey, and a pinch of salt, then toss with cabbage until lightly coated.
Mix the sauce: Stir together sour cream, mayonnaise, hot sauce or adobo, lime zest, lime juice, grated garlic, and a pinch of salt until smooth.
Cook the fish: Heat a large nonstick skillet over medium-high with a light drizzle of oil; cook fish 2–3 minutes per side until opaque and flaky. Transfer to a plate and break into large chunks if needed.
Warm the tortillas in a dry skillet 20–30 seconds per side and keep wrapped in a towel.
Assemble tacos: Spread sauce on tortillas, add fish, slaw, avocado, and red onion; finish with extra cilantro and a squeeze of lime.