itcoderr

This plugin gives you a way to choose what widgets display on each page/post of your website. The plugin’s custom sidebars provides a way, using that you can display custom widget configurations on any page, post, post type, or archive page.
Features
<ul>
<li>Unlimited custom widget configurations</li>
<li>Custom widget for individual post, page etc..</li>
<li>Sorting sidebar</li>
<li>Many more</li>
</ul>

Acquaintsoft sidebar generator

Create custom widget configurations for every page/post on your website.

oceanwp

Amit Singh

Generates an unlimited number of sidebars and place them on any page you wish. Go to Theme Panel > Sidebars to create your custom sidebars. 
This plugin requires the <a href="https://oceanwp.org/" rel="nofollow ugc">OceanWP</a> theme to be installed.

Ocean Custom Sidebar

This little free plugin allowed me to easily add any Elementor Library Item to any menu in any area. Show video's, products, forms anything you like in your menu's of sidebars.

Really, REALLY useful!

Do NOT underestimate it's power!

Generates an unlimited number of sidebars and place them on any page you wish. Go to Theme Panel > Sidebars to create your custom sidebars.

Acquaintsoft sidebar generator vs Ocean Custom Sidebar