by Diana van de Laarschot on WordPress.org
Dynamic menus: List all posts from a category in your menu. Also works for tags, custom taxonomies as well as pages and custom post types.

Go to Appearance > Menu to enable/disable and set the options for the replacement of Category / Post Tag links by their posts.
The default custom menu in WordPress only allows adding a link that leads to a list of posts and pages belonging to a taxonomy (category, tag, etc). If you want to list the posts and pages themselves and if you want WordPress to do this automatically for you, then I hope you will find this plugin useful.
Also works for custom taxonomies and custom post types
NEW: CPCM V3 now provides support for Full Site Editing with the Gutenberg Block Editor
WARNING: Coming from version 1.x? There are breaking changes, read the changelog before upgrading.
Enable the plugin and go to either Appearance > Menus or Appearance > Customize or Appearance > Editor. Add a category (or other taxonomy like tag or custom) to the menu. Next, you can choose if you would like to replace the category by the posts or pages themselves.
For each Category in your menu, you now have the following extra configuration options:
You can control the title of the menu items generated by the plug-in with the following wildcards: