Pulse shrimp, panko, egg, cilantro, lime juice, soy sauce, sesame oil, Sriracha (if using), and salt in a food processor.
Form mixture into 12 patties.
Lightly coat patties, cut side of buns, and the grill rack (or nonstick skillet) with cooking spray. Over medium heat, cook patties, turning, until golden brown and cooked through, about 5 minutes per side. Toast buns on grill for 2 minutes. Place patties on buns and top with lettuce and cucumbers.