Antonio D.

Daniil Zhitnitskii

amyrotos

Vasilis Georgoudis

WordPress gives you the ability to add metadata to your sites thus helping Google and other search engines to recognise it. The problem comes if you want to expand.
All in one metadata, extends the functionality of WordPress and gives you the flexibility to add more metadata in your sites, taking advantage of the schema markup.
https://github.com/my-language-skills/all-in-one-metadata
<h3>Disclaimers</h3>
The All in one metadata plugin is supplied “as is” and all use is at your own risk.
All in one metadata is under development. Version 1.0 is stable but is an start. Soon much more possibilities.

All in one metadata

Extended Metadata for Wordpress and PressBooks.

Tim van Iersel

Adds custom field to the post & pages editor for custom JSON-ld schema markup also known as structured data. The plugin also validates if the JSON is formated correctly. <a href="http://coderisk.com/wp/plugin/websitescanner-custom-schema/RIPS-8iSfZmxGFd" rel="nofollow ugc"></a>
Add your own JSON-ld on every page, post and custom post without the <code><script></code> to show your own custom Schema markup.
Works well with the following plugins:
<ul>
<li><a href="https://wordpress.org/plugins/remove-schema/" title="Remove Schema WordPress plugin" rel="ugc">Remove Schema</a></li>
</ul>
Usecases:
With the combination of the WordPress plugin it’s easy to overwrite the schema on a specific page. 
If a plugin like Yoast SEO or other plugin or theme that generates schema you can disable the schema and add your own custom schema to the page.

Websitescanner Custom Schema

Adds custom field to the post & pages editor for custom JSON-ld schema markup also known as structured data.

All in one metadata vs Websitescanner Custom Schema