Allow cream cheese, cheddar cheese, and butter to stand at room temperature for 30 minutes. In a food processor, combine cream cheese, cheddar cheese, butter, half-and-half, and orange peel. Cover and process until mixture is combined but still slightly chunky. Transfer mixture to a bowl.
Stir the 1/3 cup chopped pecans and the 1/4 cup chopped green onions into the cheese mixture. Cover; freeze for 15 to 20 minutes or until mixture is easy to handle. Shape mixture into a ball. Wrap with plastic wrap and chill for at least 4 hours.
Let cheese ball stand at room temperature for 15 minutes. Roll cheese ball in the 2/3 cup parsley. Wrap in plastic wrap. Store in the refrigerator.