This plugin allows you to export your posts to CSV file, through one click, from either backend or frontend. Works with custom post types, custom taxonomies and custom fields.
You can select post type, with its custom fields, that you wish to export, from the Tools >> Export Posts page.
“You must choose the post type and save the settings before downloading CSV. Once the page reloads, you will see the connected taxonomies and custom fields for the post type.”