prebhdevsingh

The purpose of this plugin is very simple – when a post is published, it will fetch the first remote/external image that is referenced. The image that is retrieved is then attached to the post as the featured image. There are no settings to configure.
Please do not use this plugin to violate copyrights.
Sample uses: You maintain multiple blogs; copy paste the post contents from one blog to the other and this plugin will automatically save the first external image to the second blog. There is no need to re-upload images to multiple sites.
This plugin can also retrieve and save images from sites like Flickr, Facebook, Picasa, etc.

Auto Save Remote Image

This plugin automatically downloads the first remote image from a post and sets it as the featured image.

Fernan Díez

WordPress plugin for downloading automatically first remote image from a post and setting it as a featured image (when the post is saved as a draft or updated).
The purpose of this plugin is very simple: when a post is saved as a draft (not published) or updated (once published), it will fetch the first remote or external image that is referenced. The image that is retrieved is then attached to the post as the featured image. There are no additional settings to configure.
Usage
Avoid losing time in the process of setting featured image for each of your blog posts or page whenever you create new content from your WordPress blog site dashboard. This post retrieves the first remote or external image of your post and uses it as a featured image.
If you maintain multiple blogs, just copy paste the post contents from one blog to the other and this plugin will automatically save the first external image to the second blog. There is no need to re-upload images to multiple sites.
This plugin can also retrieve and save images from sites like Flickr, Facebook, Picasa, or any other image stock site once you have added it in your post editor just saving that single post. Remember that hotlinking is not a good practise.
No longer overwriting a post existing featured image function added.
Credits
<ul>
<li>Based on <a href="https://wordpress.org/plugins/auto-save-remote-images/">Auto Save Remote Image Plugin</a> created by Prebhdev Singh</li>
<li>New function added from <a href="https://github.com/cristoslc/wp-auto-save-remote-image" rel="nofollow ugc">WP Auto Save Remote Image Plugin</a> created by Cristos L-C.</li>
</ul>
Please do not use this plugin to violate copyrights. Don’t be evil.

Auto Save Remote Images (Drafts)

WordPress plugin for downloading automatically first remote image from a post and setting it as a featured image (when is saved as a draft or updated)

Auto Save Remote Image vs Auto Save Remote Images (Drafts)