omerk

<a href="http://fancybox.net/" rel="nofollow ugc">Fancybox</a> is a tool for displaying images, html content and multi-media 
in a Mac-style “lightbox” that floats overtop of web page. It was built using the jQuery library.
This plugin inserts the necessary elements required to run Fancybox on your blog. It also groups 
images within posts using rel attributes. (Based on the code found on <a href="https://wordpress.org/support/topic/automatic-adding-lightbox-rel-and-group-to-images-in-posts" rel="ugc">this</a> 
forum thread)
To disable Fancybox per post: Add a custom field called ‘nofancybox’ and set it’s value to ‘true’. 
Instructions on how to add custom fields to posts can be found at <a href="https://codex.wordpress.org/Custom_Fields" rel="nofollow ugc">this</a> 
codex article.

Fancyboxify

This simple plugin enables Fancybox on image links. It groups all images within a single post and can also be disabled per post.

Arno Welzel

This plugin integrates PhotoSwipe to WordPress. All linked images in a post or page will be displayed using PhotoSwipe, regardless if they are part of a gallery or single images.
More about the original version of PhotoSwipe see here: <a href="http://photoswipe.com" rel="nofollow ugc">http://photoswipe.com</a>
You can also display EXIF data from supported image types.
As of version 4.0.0 this plugin requires at least WordPress 5.3 and PHP 7.0. Older PHP version will cause problems. In this case you have to upgrade your PHP version or ask your hoster to do so. Please note that WordPress itself also recommends at least PHP 7.4 – see <a href="https://wordpress.org/about/requirements/" rel="ugc">https://wordpress.org/about/requirements/</a>.
Please keep in mind: not the visible thumbnail is relevant, but only the image link. Images should always be linked to the file and not to the attachment page. Since version 5.6.1 there is an option to fix attachment links which can be enabled if needed – however this may slow down your website since then all links on a page will be checked if they are attachment links.

Lightbox with PhotoSwipe

Amazing lightbox plugin

Integration of PhotoSwipe (http://photoswipe.com) for WordPress.

Fancyboxify vs Lightbox with PhotoSwipe