Soak 12 wooden skewers in water for 30 minutes to prevent burning on the grill. Heat a grill to medium-high.
In a medium bowl, combine the shrimp, lime zest, lime juice, salt, and black pepper. Set aside to marinate while the grill heats.
Drain the skewers and pat dry with a paper towel. Mist them with cooking spray. On each of 4 skewers, thread 4 shrimp. On the remaining skewers, thread the shishito peppers and tomatoes, alternating them. Mist the skewers with cooking spray.
Grill the shrimp skewers for 2 minutes on each side, taking care not to burn shrimp. Grill the vegetable skewers until the skins are slightly blistered and charred, 4 to 5 minutes total.
Remove the skewers from the grill and brush with Chimichurri Sauce; serve more sauce on the side.
