Preheat the oven to 400°F.
Grate the zest from the lemon. Halve the lemon and set aside.
Place the chops in a shallow dish with 2 tablespoons of the oil, the chopped garlic, fennel seeds, rosemary, lemon zest, and about 1½ teaspoons pepper. Season the chops liberally with salt and slather the porchetta seasoning evenly all over the chops, turning to coat both sides. Let stand for 30 minutes.
Meanwhile, in a large bowl, combine the fresh fennel, shallots, potatoes, smashed garlic, remaining 2 tablespoons oil, and salt and pepper to taste. Toss to coat, then arrange on baking sheets. Place the lemon halves cut side down on the baking sheet. Roast until the potatoes are crispy and the fennel and shallots are caramelized at the edges, about 35 minutes.
Heat a cast-iron skillet over medium-high heat. Add the chops to the hot pan and brown for 3 to 4 minutes on each side. Transfer to the oven and roast for about 8 minutes. Remove from the oven and douse the skillet with the wine. Squeeze the juice from the roasted lemon halves over the top.
Serve the chops with the roasted vegetables alongside.