dmallon

The Post To Sidebar plugin makes it easy to display post content in the sidebar areas of your site. Once the widget is activated, a multi-select dropdown of all your published pages appears on post editing screens. Select the pages upon which you want the post to be displayed and the post will appear on those pages.
There are options to hide the post title in the output and to show the content as an excerpt.

Post To Sidebar

A WordPress plugin/widget that gives you the ability to put content (posts and custom post types) in your sidebar.

toddhalfpenny

The easiest, and highest rated way to Add Widgets to Posts and/or Pages. Create unlimited dynamic sidebars (widget areas) and insert these into a WordPress post or page.
Create as many widget areas (Turbo Sidebars) from the settings menu, and these can be used multiple times.
Each sidebar can be called independently by a shortcode, and you can call more than one per post/page.
Sidebars can be included in the post/page by using a shortcode like the following, where <code>x</code> is the name of the sidebar.
<pre><code>[widgets_on_pages id=x]
</code></pre>
<blockquote>
With the <a href="https://datamad.co.uk/wordpress-plugins/widgets-on-pages/" rel="nofollow ugc">PRO</a> version the widgets can be inserted simply with clicks-not-code using a wizard in the visual editor. This version also includes layout options to easily set the widgets in columns/grid presentation.
Pro version also supports the configurable option to automatically add widgets to all your posts and/or pages. Choose the layout options and whether to add the sidebar and widgets before or after the content. Ideal for adding lists of related posts to the end of every post. Each post and page can also be individually excluded from the auto-inclsion of the widgets.
<a href="https://datamad.co.uk/wordpress-plugins/widgets-on-pages/" rel="nofollow ugc">Pro version</a> key features 
 * Responsive Horizontal/Column/Grid layout 
 * Auto insert in Header, Content, or Footer 
 * Priority Support
</blockquote>
Basic In-Content Instructions
<ul>
<li>Create a Turbo Sidebar, these are your special widget containers</li>
<li>Add widgets to the Turbo Sidebar in the same way as you do for normal sidebars</li>
<li>If using the visual editor use the Add Turbo Sidebar button to add the Shortcode into your post or page where you’d like it to appear.</li>
</ul>
The sidebars can also be added to any theme, using template tags. This is an ace way to add widgets/sidebars to a theme’s header and footer (or any other part of a theme).
Demo Video
<iframe loading="lazy" class="youtube-player" width="750" height="422" src="https://www.youtube.com/embed/w2LfCihCqRI?version=3&rel=1&showsearch=0&showinfo=1&iv_load_policy=1&fs=1&hl=en-US&autohide=2&wmode=transparent" allowfullscreen="true" style="border:0;" sandbox="allow-scripts allow-same-origin allow-popups allow-presentation allow-popups-to-escape-sandbox"></iframe>
Current Features Include
<ul>
<li>Highest Rating – 122 5* Reviews</li>
<li>No Coding needed</li>
<li>Create unlimited sidebars</li>
<li>Place them in posts/pages/custom post types</li>
<li>Add to themes using template tags</li>
<li>Works with ALL widgets and themes (let us know if you have an issue)</li>
</ul>
Recent Reviews
∗ ∗ ∗ ∗ ∗ Just purchased PRO version and well worth the money. – <a href="https://wordpress.org/support/topic/extremely-useful-plugin-19/" rel="ugc">@artmuns</a>
∗ ∗ ∗ ∗ ∗ Works as advertised + timely response to support request – <a href="https://wordpress.org/support/topic/works-as-advertised-timely-response-to-support-request/" rel="ugc">@3cstudio</a>
∗ ∗ ∗ ∗ ∗ Saving me HOURS of work – <a href="https://wordpress.org/support/topic/saving-me-hours-of-work/" rel="ugc">@andynick</a>

Widgets on Pages

The easiest and highest rated way to Add Widgets or Sidebars to Posts and Pages using Visual editor,  shortcodes or template tags.

Post To Sidebar vs Widgets on Pages