Start by boiling the potatoes in salted water until fork tender while you prep the meatballs.
In a small bowl, combine the breadcrumbs and milk and let the mixture sit for a few minutes. This helps keep the meatballs soft and tender instead of dense.
In a large bowl, mix together the ground beef, ground pork, soaked breadcrumb mixture, onion, egg, salt, pepper, and nutmeg until just combined.
Roll the mixture into evenly sized meatballs, then cook them in the air fryer or oven until browned and cooked through.
While the meatballs cook, make the sauce. Melt the butter in a large skillet, whisk in the flour, and cook for a minute or two until lightly golden.
Slowly whisk in the beef broth, then add the cream and let the sauce simmer until thickened and smooth.
Add the cooked meatballs to the skillet and let everything simmer together for a few minutes so the sauce coats the meatballs and the flavors come together.
Drain the potatoes, then mash them with butter, milk, salt, and pepper until smooth and creamy.
Serve the Swedish meatballs over mashed potatoes with cranberry sauce and fresh herbs on top.