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.

Noor Alam

<a href="https://noorsplugin.com/wordpress-fancybox-plugin/" rel="nofollow ugc">WP fancybox</a> plugin adds fancybox lightbox effect to your WordPress website. The lightbox looks great on desktop as well as mobile devices.
<h3>WP fancybox Features</h3>
<ul>
<li>Responsive lightbox popup using fancybox</li>
<li>Designed with a mobile first approach so it looks great on desktop, mobile and tablet devices</li>
<li>Quick and easy setup</li>
<li>Open lightbox popup from either a text link or a thumbnail image link</li>
<li>YouTube video popup</li>
<li>Vimeo video popup</li>
<li>Use a simple shortcode to pop up content in lightbox</li>
</ul>
<h3>How to Use WP fancybox</h3>
Image in lightbox
Create a new post/page and use the following shortcode to create a text/image link which will open lightbox once clicked:
<pre><code>[wp_fancybox_media url="https://example.com/wp-content/uploads/images/overlay.jpg" hyperlink="click here to pop up image"]
</code></pre>
here, url is the link to the media file that you wish to open in lightbox and hyperlink is the anchor text/image.
<pre><code>[wp_fancybox_media url="https://example.com/wp-content/uploads/images/overlay.jpg" hyperlink="https://example.com/wp-content/uploads/images/thumb.jpg"]
</code></pre>
YouTube video in lightbox
<pre><code>[wp_fancybox_media url="https://www.youtube.com/watch?v=Vpg9yizPP_g" hyperlink="click here to pop up youtube video"]
</code></pre>
Vimeo video in lightbox
<pre><code>[wp_fancybox_media url="https://vimeo.com/1084537" hyperlink="click here to pop up vimeo video"]
</code></pre>
Alternate Text for an Image
<pre><code>[wp_fancybox_media url="https://example.com/wp-content/uploads/images/overlay.jpg" hyperlink="https://example.com/wp-content/uploads/images/thumb.jpg" alt="Thumbnail image description"]
</code></pre>
Custom CSS
You can specify your own CSS class in the shortcode to customize a text/image link.
<pre><code>[wp_fancybox_media url="https://www.youtube.com/watch?v=Vpg9yizPP_g" hyperlink="click here to pop up youtube video" class="custom_class"]
</code></pre>
Multiple CSS classes can be separated with a space. For example:
<pre><code>[wp_fancybox_media url="https://www.youtube.com/watch?v=Vpg9yizPP_g" hyperlink="click here to pop up youtube video" class="custom_class custom_class2"]
</code></pre>
For detailed documentation please visit the <a href="https://noorsplugin.com/wordpress-fancybox-plugin/" rel="nofollow ugc">WordPress fancybox</a> plugin page

WP fancybox

View image, YouTube video, Vimeo video, inline HTML in lightbox. Add fancybox lightbox effect to your WordPress site.

Fancyboxify vs WP fancybox