In a spice grinder, combine 1½ teaspoons salt, 1 teaspoon black pepper, the rosemary, fennel seeds and pepper flakes. Process to a fine powder, about 10 seconds. Measure ½ teaspoon into a medium bowl and set aside. Sprinkle the remainder onto both sides of the pork chops, then rub the seasonings into the meat.
In a 12-inch skillet over medium-high, heat 2 tablespoons of oil until barely smoking. Add the chops and cook until well browned on the bottom, 3 to 5 minutes. Flip and cook until the centers reach 135°F, another 3 to 4 minutes. Transfer to a platter and tent with foil. With the pan still over medium-high, add ¼ cup water and scrape up any browned bits. Add the butter and whisk until incorporated, then stir in 1 tablespoon of lemon juice. Taste and season with salt and black pepper. Remove from the heat and cover to keep warm.
To the bowl with the spice mix, whisk in the remaining 1 tablespoon oil and the remaining 2 tablespoons lemon juice. Add the fennel, scallions and parsley, then toss to combine. Taste and season with salt and pepper. Pour the sauce over the chops and serve with the fennel salad.