Season pork chops with salt and pepper. In a large skillet, heat oil over medium-high until shimmering.
Add the pork chops to skillet and sear, without moving, until dark golden, 4 to 5 minutes per side. Lower heat, cover pan and cook the pork chops for 3 minutes longer. Transfer to a plate.
Return the skillet to the stove and reduce heat to medium. Add onions and cook until lightly golden, 2 to 3 minutes. Add green beans, red-pepper flakes and salt, stirring everything to coat with pan juices
Making space in the skillet, return pork chops to pan, surrounding them with beans. Add feta, mint and basil. Cover and cook over low heat until pork chops are just cooked through, 3 to 6 minutes longer.
Drizzle or squeeze lemon juice over the dish and serve.