In a large nonstick skillet over high heat, warm oil, about 1 minute; swirl to evenly coat bottom of pan. Add scallops, flat side down, and cook until browned on both sides, 2 to 3 minutes per side. Season with salt. Transfer to plate.
Reduce heat to medium; add onion, and cook, stirring, until browned, 1 to 2 minutes. Add ginger, snap peas, and 1/2 cup water; cook, stirring occasionally, until vegetables are crisp-tender and water has evaporated, about 3 minutes.
Remove from heat; add scallops, lime juice, chili sauce, and cilantro leaves. Toss to evenly coat. Season with salt, if desired.
