farvehandleren

Make a sidebar and place it anywhere in post or page with shortcode.
Shortcode :
You will be get the shortcode after creating the sidebar
Manage Sidebars : 
In wp dashboard , there is a menu called “Widget Area” to Add and Remove a Sidebar. 
As you will add a sidebar, you will see the shortcode to display the sidebar and then you will be able to see a new sidebar area in “Widgets Area”. 
Just drag any widget in the sidebar and display through the shortcode in a page, template or anywhere.
Display Sidebar
After creating a sidebar, you will be provided a shortcode like : [ri_custom_sidebar 1], [ri_custom_sidebar 2] …
Just write in wordpress pages or posts where you want to display : [ri_custom_sidebar 1] (for example)
Or use this php code to display in a template : echo do_shortcode(‘[ri_custom_sidebar 1]’); (for example)

Widget Area Builder

Make a sidebar and place it anywhere in post or page with shortcode.

ShinichiN

This plugin enables you to create unlimited custom sidebar/widget areas and switch existing areas. You can do this without touching your theme.
This plugin utilizes term meta api and so it works only with WordPress 4.4 and above.
Your theme needs to use <code>is_active_sidebar()</code> when calling <code>dynamic_sidebar()</code> function.
This will work.
<pre><code>if ( is_active_sidebar( 'sidebar-1' ) ) {
 dynamic_sidebar( 'sidebar-1' );
}
</code></pre>
This doesn’t work.
<pre><code>dynamic_sidebar( 'sidebar-1' );
</code></pre>
If you only want to output your custom sidebar, put this code on where you want to display the sidebar in your theme.
<pre><code>do_action( 'dynamically_dynamic_sidebar' );
</code></pre>
<a href="https://github.com/ShinichiNishikawa/Dynamically-Dynamic-Sidebar/" rel="nofollow ugc">This Plugin published on GitHub.</a>
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Dynamically Dynamic Sidebar

Create unlimited custom sidebar/widget areas and switch existing areas depending on post, page, custom-post-type post, categories, tags and custom tax …

Widget Area Builder vs Dynamically Dynamic Sidebar