patrys

This plugin will add a copyright footer to your feeds. Each footer contains a permalink, author info and the license.
Currently footers are not appended to the excerpts as it’s not common to steal these.

RSS License

Allows one to include the wpLicense copyright in blog feeds.

hiroprot

Terms Before Download adds a shortcode that can be used instead of HTML anchors to link to downloadable files. If such a link is clicked a popup dialog shows terms and conditions (EULA) which must be accepted for the download to start.
The terms and conditions are read from a WordPress page. That way there is only a single place to maintain the terms and they can easily be displayed independently of the plugin.
The plugin supports Google Analytics to keep track of the number of downloads. Supported GA scripts: ga.js, analytics.js.
An example of the plugin in action can be found here: https://helgeklein.com/download/
Usage
Add the shortcode tbd_terms once (!) to each page or post where terms need to be displayed and configure the ID of the page that contains the terms. Example:
[tbd_terms terms_page_id=5670]
The page ID is part of the URL when editing a page in the admin UI. Example: https://domain.com/wp-admin/post.php?post=5670&action=edit
Create a link to a downloadable file like this:
[tbd_link url=\”URL\”]link text[/tbd_link]
Parameters
The following parameters can be used with the shortcode tbd_terms:
<ul>
<li>terms_page_id: ID of the terms page displayed in the dialog [required] </li>
<li>dialog_title: The title of the dialog to be displayed [optional] </li>
<li>class: CSS class of the div enclosing the dialog content [optional] </li>
<li>padding: Padding between the dialog frame and the inner content [optional] </li>
<li>width: Width of the dialog [optional] </li>
<li>ok_button_text: Text for the OK button [optional]</li>
</ul>
The following parameters can be used with the shortcode tbd_link:
<ul>
<li>url: The URL to link to [required]</li>
<li>text: Link text [required if text is not enclosed]</li>
<li>gacategory: Google Analytics Category [optional]</li>
<li>gaaction: Google Analytics Action [optional]</li>
<li>galabel: Google Analytics Label [optional]</li>
</ul>

Terms Before Download

Shows a popup dialog with terms and conditions (EULA) that must be accepted before a file can be downloaded

RSS License vs Terms Before Download