In a large skillet over medium-high heat, heat 1 tablespoon oil. Add asparagus; season with ½ teaspoon salt. Cook, stirring occasionally, until asparagus are tender but still crisp, 8 to 10 minutes. Transfer to a plate.
In same skillet over medium heat, cook butter, garlic, onion powder, red pepper, and remaining 1 tablespoon oil until butter is melted. Add shrimp; season with ½ teaspoon salt. Cook until shrimp are pink and cooked through, 1 to 2 minutes per side. Remove from heat and stir in asparagus. Add lemon zest, lemon juice, and parsley and toss to combine.