Pound pork steaks between 2 layers of plastic wrap to ¼" thick. Place flour in a shallow bowl. Lightly beat eggs in another shallow bowl. Toss breadcrumbs and cornstarch in a third shallow bowl; season with kosher salt and pepper.
Working one at a time, season cutlets with kosher salt and pepper, then dredge in flour, shaking off excess. Transfer to bowl with egg and turn to coat. Lift from bowl, allowing excess to drip off. Coat with breadcrumb mixture, pressing to adhere.
Heat vegetable oil in a large skillet over medium-high. Working in 2 batches, cook cutlets, shaking pan occasionally, until golden brown and cooked through, about 3 minutes per side. Transfer to a wire rack; season with sea salt.
Combine fennel, fennel fronds, asparagus, onion, and parsley in a medium bowl. Toss with lemon juice and olive oil; season with kosher salt and pepper. Serve salad alongside cutlets with lemon wedges for squeezing over.