Elmseeker

This plugin simply adds a copyright notice to the bottom of every post on 
your WordPress site.
Example: (c) Copyright (the year the post was made), (the author), All 
Rights Reserved. Written For: (the name of your blog)
More features, like custom text, coming soon.

Post Copyright Plugin

This plugin simply adds a copyright notice to the bottom of every post on

Subodh Ghulaxe

This plugin provides a quick and easy way to disable right click, disable cut, copy, paste, disable view source and disable image drag & drop.
Using this plugin you can stop plagiarism, stop visitor form downloading images from your website and be sure about your websites content protection.
<h3>Features</h3>
<ul>
<li>Disable right click.</li>
<li>Show disabled message on right click.</li>
<li>Disable cut, copy and paste.</li>
<li>Show disabled message on cut, copy and paste.</li>
<li>Disable image drag & drop.</li>
<li>Show disabled message on image drag & drop.</li>
<li>Disable view source.</li>
<li>Show disabled message on view source.</li>
<li>Disable CTRL+C, CTRL+X, CTRL+V, CTRL+U, ⌘+C, ⌘+X, ⌘+V, ⌘+Option+I, ⌘+Option+U</li>
<li>More content protection options are coming in upcoming releases.</li>
</ul>

Content Copy Protection & Disable Right Click

Verified this plugin with WordPress 5.7.2 version.

Working perfectly with WordPress 5.7.2

This plugin provides a quick and easy way to disable right click, disable cut, copy, paste, disable view source and disable image drag & drop.

Post Copyright Plugin vs Content Copy Protection & Disable Right Click