In a bowl, mix mole and 1/3 cup water.
Rinse fish and pat dry; cut into 1-inch chunks and mix with mole sauce. Thread swordfish, pieces touching, onto thin metal skewers.
In a small bowl, mix mayonnaise with 2 tablespoons water.
Lay tortillas on a barbecue grill over a solid bed of hot coals or high heat on a gas grill (you can hold your hand at grill level only 2 to 3 seconds), close lid on gas grill. Turn to heat both sides, 1 to 2 minutes total. When tortillas are hot, stack in a towel-lined basket to keep warm.
Lightly oil grill and lay skewers on it. Barbecue fish (close lid on gas grill) until opaque but moist-looking in center of thickest part (cut to test), about 8 minutes; turn once to cook evenly.
Put skewers on plates. To assemble each taco, top a tortilla with fish chunks, cabbage, tomatoes, mayonnaise mixture, and lime juice and salt to taste. Fold tortilla around filling to eat.