Sanam Maharjan

This is a plugin for converting lots of posts or pages to a custom post type (or vice versa). In the ‘convert from…’ select option you will get the lists of all the post types stores in your current database and in the ‘convert to…’ option you will get the list of all the current registered post types. In addition to this you can also convert from one taxonomy to another and the lists are populated just as that of post types.

Post Type Convertr

A bulk conversion utility for post types and taxonomies.

netbiel

This plugin ads some extra options to your Customizer (like social icons), registers taxonomies and custom posts types for: 
– Portfolio items 
– Testimonials 
– FAQ 
– Team Members
This plugin doesn’t change how new post types are displayed in your theme. e.g You’ll need to add templates for archive-portfolio.php and single-portfolio.php if you want to customize the display of portfolio items. 
In the theme integrated with smartlib library you don’t need do anything

Smartlib Tools

Useful post types and customizer options.

Post Type Convertr vs Smartlib Tools