Built-in Addons:

Post Duplicator

One of the essential features when it comes to managing content, is to be able to duplicate a post or page. WordPress doesn’t have such feature by default. But, with GD Press Tools Pro, you will get option to duplicate any post or page (including custom post types). You have options to control prefix and suffix for the duplicated post title, options on how to deal with taxonomy terms, meta data and option for deep copy (to copy hierarchy).

Post Duplicate Settings
Post Duplicate Settings