Mario Peshev

WARNING: This script alters the database content so use at your own responsibility! Backup your database first.
Shortcode Freezer. If you have a website with content based on shortcodes 
and this content generates some static data (i.e. authors, pricing, buttons and other listing that just provides html markup with a ‘short code’), 
then feel free to convert that to the static values before switching themes. This would evaluate the shortcodes and generate the HTML markup and replace the database posts with the evaluated content.
Keep in mind that it would not work with dynamic listings that generate dynamic content – they would ‘freeze’ and will not be dynamic anymore.
You can switch themes without worrying about shortcode compatibility. Once the markup is generated and embedded into posts, your data would be visible and you can style the markup in the new theme.

DX Shortcode Freezer

Converting all static shortcodes to their static representation at the moment of generation. This plugin could alter your database posts.

Studiofreya

SF Generate Tags is a plugin that helps generate tags for posts. It scans the names of all attached images and/or the post content (text) and places the resulting tags in the built-in WordPress “Tags Widget” in the post editor. 
The plugin analyzes collected words and picks out the most suitable for tags. 
All tags are then sorted in descending order and posted into the Tags widget. 
If you don’t like a tag which has been discovered and want to delete them, you can just click the X button and save post without them. 
The plugin doesn’t mess with your existing tags. It preserves all your existing tags for the post. All the actions can be easily undone.
This plugin should work with any language. It’s filtering algorithm is designed for English. All other languages will have all the words be added as tags.
<a href="https://studiofreya.com/wordpress/sf-generate-tags/" rel="nofollow ugc">SF Generate Tags website</a>
<h4>Features:</h4>
<ul>
<li>Easy to use from the admin panel for post edit </li>
<li>Choose to generate tags from attached images or post text or both</li>
<li>Exclude words that you don’t want to be tags</li>
<li>Easy to remove all undesirable tags</li>
<li>All actions can be undone</li>
<li>Existing tags are preserved</li>
<li>Add other tags later</li>
<li>Regenerate tags after updating the post (or not)</li>
<li>Limit number of generated tags</li>
</ul>

SF Generate Tags

Generate tags for posts from images or/and post text.

DX Shortcode Freezer vs SF Generate Tags