Place balsamic vinegar, jalapeno pepper, cilantro, zest and ginger in a blender and blend until the mixture is smooth.
Add the olive oil and blend to emulsify.
Pour half the mixture into a bowl (reserve the other half for drizzling later).
Marinade the fish in the bowl of mixture for 30 minutes to 1 hour.
After the fish is marinated, discard the marinade.
Heat the grill to high.
Skewer the swordfish and grill for 4-5 minutes each side until just cooked through.
Spoon the reserved sauce onto a platter and top with skewers. Drizzle more on top.
Season with salt and pepper then serve.