In a large bowl, combine chicken, onion, garlic, feta, breadcrumbs, egg, parsley, oregano, dill, lemon zest from 1 lemon, salt, and pepper. Mix until well combined.
Form 1.5-inch balls with the meat mixture. Heat oil in a skillet over medium heat then add meatballs. Cook until golden on one side, then turn and repeat until cooked through, 3 to 4 minutes per side.
Remove meatballs and set aside. In the same pan, add orzo and chicken broth. Bring to a boil, reduce to low, and simmer 8–10 minutes until tender. Drain if excess liquid remains.
Stir in lemon juice and zest from 1 lemon, fresh parsley, Parmesan, salt, and pepper until cheese melts.
Serve orzo in bowls topped with meatballs. Garnish with extra feta, parsley, or Parmesan.