If frozen, thaw the salmon overnight in the refrigerator.
Mix the Szeged fish rub, ground cumin, and chili powder in a small bowl.
Brush the salmon on both sides with the olive oil, then rub the spice mixture evenly over the fillet.
Let the salmon sit at room temperature while you prepare the slaw.
Thinly slice the green and red cabbage, slice the green onions, and chop the cilantro if using.
Whisk together mayonnaise, fresh lime juice, Green Tabasco Sauce, and Vege-sal or salt to make the slaw dressing.
Toss the cabbage and green onions with about half of the dressing until evenly coated, then stir in chopped cilantro if using.
Reserve the remaining dressing to drizzle over the tacos.
Preheat the air fryer to 400°F (200°C). Place the salmon on parchment or directly in the air fryer basket and cook for about 6 minutes without turning, until cooked through.
Alternatively, grill or roast the salmon using your preferred method if not using an air fryer.
While the salmon cooks, warm each tortilla in a dry hot skillet for 30–60 seconds per side.
Remove the salmon and flake it into bite-sized pieces with a fork.
Assemble the tacos by placing some slaw on each warmed tortilla, topping with flaked salmon, and drizzling extra dressing over the tacos.
Serve immediately with lime wedges if desired.