Slice cucumbers thinly. For extra crispness, sprinkle lightly with salt, let sit 10 minutes, then pat dry.
Place cucumbers in a bowl with green onions and any optional vegetables.
In a small bowl, whisk together soy sauce, rice vinegar, sesame oil, honey, garlic, red pepper flakes, and ginger (if using).
Pour the dressing over the cucumbers. Gently toss until evenly coated.
Sprinkle toasted sesame seeds and optional peanuts or herbs on top.
Chill 10–15 minutes before serving for flavors to meld.