jeff.cave

This plugin provides a “Sub Page” widget. It lists all of the pages which are children of the current page. If there are no children, it will not display.
Options include:
<ul>
<li>title (obviously)</li>
<li>“No Sub-pages” text instead of blank (configurable)</li>
<li>hide widget when no sub-pages</li>
<li>show siblings when no sub-pages</li>
</ul>
While this is a small widget, I have attempted to make this as configurable as possible, with clean and efficient code (this is a small widget, and shouldn’t slow your site down).

PS Sub-pages

Shows the child pages of the current page. Configurable title, show siblings (or not), and "no child" text

Gecka

PHP 5 required. Please be sure to check your PHP version before marking the plugin as broken.
Submenu enhances the WordPress 3.x navigation system. When you have a website based on WordPress with a lot of pages, but you need a custom menu, it can be tedious to have to add a menu entry for each page created. Submenu just does it automatically.
Submenu also allows you to put menus or portion of menus anywhere in your site: sidebar, templates or page contents.
Languages available: english, french
Contribute: <a href="https://github.com/Gecka-Apps/Wordpress_Gecka_Submenu" rel="nofollow ugc">This plugin is on GitHub</a> !
<a href="http://gecka-apps.com/wordpress-plugins/gecka-submenu-pro/" title="Discover the pro version" rel="nofollow ugc">Discover the pro version</a> by checking out the <a href="http://www.youtube.com/watch?v=DHjMfD-k2Mo" rel="nofollow ugc">Gecka Submenu Pro video</a>:
<iframe loading="lazy" title="What if you could ?" width="750" height="422" src="https://www.youtube.com/embed/DHjMfD-k2Mo?feature=oembed" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share" referrerpolicy="strict-origin-when-cross-origin" allowfullscreen></iframe>

Gecka Submenu

Works fine for me

Submenu autopopulates any nav menu page item with its children and allows to put menus, or portion of menus, anywhere in your site.

PS Sub-pages vs Gecka Submenu