Preheat the oven to 400°F. Line a large baking sheet with parchment paper and lightly spray the parchment with nonstick cooking spray.
If your wonton wrappers are not already cut, slice 30 wonton wrappers diagonally to make triangles.
Arrange the 30 wonton triangles in a single layer on the prepared baking sheet without overlapping. Lightly spray the tops with cooking spray, season with kosher salt to taste, and, if using, sprinkle 1/2 teaspoon black sesame seeds evenly over them.
Bake the wonton chips for 6–8 minutes, watching closely, until they are lightly browned and crispy. Remove from the oven.
Transfer the baked chips to a serving platter or allow them to cool on the baking sheet for 1–2 minutes so they crisp fully.
While the chips bake (or immediately after), make the cream cheese sauce: in a medium bowl whisk together 4 ounces softened cream cheese, 5 tablespoons heavy cream, 3/4 teaspoon soy sauce, 1/2 teaspoon Worcestershire sauce, 1/4 teaspoon sesame oil, 1/2 teaspoon powdered sugar, and 1/4 teaspoon garlic powder until smooth and creamy.
Fold most of the 2 thinly sliced green onions into the cream cheese mixture, leaving some slices reserved for garnish.
Spread the cream cheese sauce evenly over the baked wonton chips.
Evenly sprinkle 1 2/3 cups chopped imitation crab meat over the sauced chips.
Drizzle 1/4 cup sweet chili sauce and 2 tablespoons garlic chili oil over the nachos.
Garnish with the reserved sliced green onions and a sprinkle of sesame seeds for garnish. Serve immediately.