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>
ウィジェットエリアをいくつでも定義し、カテゴリやタグ、カスタム分類ごとに差し替えたり、投稿・ページ・カスタム投稿から使いたいサイドバーを指定したりすることができます。「スクリーンショット」のタブをごらんいただくと、イメージが湧きやすいと思います。

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 …

Nick van de Veerdonk

Add 3 widget areas to the footer section to your AMP (accelerated Mobile Pages) content, fully marked up using Microdata(WPFooter). Additionally the plugin options page allows to add a fully marked up credits footer: copyrightYear, copyrightHolder and creator, see screenshots. Provides a handy Google Structured Data Testing Tool 1-click bookmarklet and an option to hide the native AMP footer.
<blockquote>
We aim to provide you with a usefull plugin, if in any way you experience difficulties or inconsistencies kindly <a href="https://jaaadesign.nl/en/blog/amp-footer-widgets/" rel="nofollow ugc">let us 
 know</a>, thank you!
</blockquote>
This plugin is actively maintained but will not be supported. I will however try to answer any questions in the comment section of the <a href="https://jaaadesign.nl/en/blog/amp-footer-widgets/" rel="nofollow ugc">plugin website</a> and create a FAQ here in the repository.
Be sure to check out our other AMP plugins!

AMP Footer Widgets

Extends the excellent AMP plugin (Automattic) by adding 3 widget areas in the footer of your website, and lots of goodies.

Dynamically Dynamic Sidebar vs AMP Footer Widgets