For marinade, combine olive oil, sun-dried tomatoes, parsley, basil, garlic, Italian seasoning, lemon zest, lemon juice, and red pepper flakes in a bowl; season with salt and pepper.
Add mozzarella balls and olives to marinade, gently tossing until well coated, and balls are mostly submerged in marinade. Cover the bowl and refrigerate for at least 2 hours or preferably overnight. If possible, stir occasionally.
Store in a tightly-covered glass jar in the refrigerator. Olive oil will solidify, so remove from the fridge about 15 minutes before serving so that olive oil can liquefy.