In a small bowl, whisk to combine 1 Tbsp olive oil, 1 Tbsp lemon juice, and 1/8 tsp salt. Add shrimp, toss to combine, and set aside to marinade.
Heat 1 Tbsp oil in a nonstick skillet over medium heat. Add onion and saute 2 minutes until it starts to soften. Add garlic and saute 2 more minutes.
Add shrimp and cook 2 minutes on each side. Stir in beans, continue cooking just until beans are warm. Add vegetable stock if more liquid is needed.
In a small bowl, whisk together the lemon vinaigrette ingredients. Pour half the dressing over the shrimp mixture and toss.
To serve, divide shrimp mixture evenly among 4 plates. Top with chopped parsley, feta, and remaining lemon vinaigrette to taste.