Place flour in a shallow dish, eggs in a second shallow dish, and Panko breadcrumbs in a third shallow dish.
Season the pork with salt and pepper on both sides.
Working with one piece of pork at a time, dredge the meat in the flour, shaking off any excess. Dip in the eggs, shaking again to remove any excess egg. Finally, coat in breadcrumbs. Repeat with remaining pork.
Heat oil in a skillet over medium-high heat. Working in batches so that you don’t overcrowd the pan, fry the breaded pork in the skillet until browned and no longer pink, about 3 minutes per side. If the breading is browning too quickly, or if the skillet starts to smoke, reduce the heat. Remove browned pork to a paper towel-lined plate. While it’s still warm, season the pork with additional salt and pepper, to taste.
Wipe out the skillet. Melt butter in the pan over medium heat. Add the mushrooms to the pan and cook until soft, about 5-7 minutes.
In a small bowl, whisk together the gravy mix, cold water and wine. Add the gravy mixture to the skillet with the mushrooms; bring to a boil over medium heat. Reduce the heat and cook, stirring constantly, for one more minute. Remove from the heat; whisk in the sour cream.
Serve the pork with mushroom gravy, fresh parsley and lemon wedges.