Default WordPress select all option only allows you to select posts or post types on the current page. For selecting more posts first you will have to click ‘Screen Options’ button (on the top right corner) and change the number of posts to show.
But entering a big number slows down the admin page and then also you cannot perform bulk actions to all posts you have on your website.
In this lesson we will show you how you can extend the select all functionality to all posts on your WordPress site instead of just posts on the current visible page.
The functionality also works with WordPress custom post types (CPTs). It works for posts, pages and custom post types. It doesn’t support terms, comments and other object types.
Start by installing and activating Bulk Actions Select All plugin in WordPress
Bulk Actions Select All is a WordPress plugin that adds another option to admin posts overview.
The option allows you to select all posts (instead of just posts on the current page) to bulk delete/restore posts.