We'll create fresh WordPress site with Assign Staff as Author for Total installed. You have 20 minutes to test the plugin after that site we'll be deleted.
Adds a new field to the post edit screen for all public post types so you can select a “Staff Member” (a post from the staff custom post type) as the “author” of the article to be displayed on the front-end. This will not actually change the author of the post itself but simply change the name displayed on the front-end in the author bio and post meta sections.
Note: This plugin is intended to be used with the Total Theme for WordPress and the Total Theme Core plugin which registers the Staff post type. If you are using it with a different theme that has a built-in staff post type or a different theme using a custom post types plugin to register the staff members, it may or may not work depending how the theme is coded. This plugin hooks into the author_link, the_author and get_the_author_description to make it’s changes.