Thinly slice the cucumber and place them in a colander set over a large bowl. Sprinkle with 2 teaspoons salt, then set aside to drain for 1 hour.
Rinse remaining salt off cucumbers under cold water, then pat dry.
In a small bowl, whisk together rice wine vinegar, ginger, sesame oil, honey, garlic, and remaining kosher salt.
In a large bowl, place drained cucumbers, onion, cilantro, chile pepper, and scallions.
Drizzle the dressing over the vegetables and toss to coat. Garnish with sesame seeds and serve immediately.
