danielpataki

Easy Featured Images allows you to assign featured images to posts much more efficiently, especially if you have a number of posts to go through. Normally you have to visit the edit page of each post, launch the media window and upload/assign the image.
With the plugin enabled you can do this from the post list screen. Everything words via AJAX so images are assigned instantly, without having to wait for pages to load. It uses the regular WordPress media box making the plugin 100% WordPress awesome.
Easy Featured Images also support WooCommerce, yay!
You can use the <code>efi/post_types</code> filter to modify the array of post types that the plugin’s functionality is assigned to. Return the final list of post types you want the plugin to be applied to:
<pre><code>add_filter( 'efi/post_types', 'my_post_type_images' );
function my_post_type_images( $post_types ) {
 unset( $post_types['page'] );
}
</code></pre>
As of 1.2.0 the plugin has an <code>efi/settings</code> filter which allows developers to change some settings. For now the only setting available is <code>show_thumbnail_preview</code> which can be set to true or false.
<pre><code>add_filter( 'efi/settings', 'my_efi_settings' );
function my_efi_settings( $settings ) {
 $settings['show_thumbnail_preview'] = false;
 return $settings
}
</code></pre>
<h4>Thanks</h4>
<ul>
<li><a href="https://tommcfarlin.com/the-wordpress-media-uploader/" rel="nofollow ugc">Tom McFarlin</a> for the basis of the Javascript that initiates the media uploader</li>
<li><a href="https://unsplash.com/colepatrick" rel="nofollow ugc">Cole Patrick</a> for the fantastic photo for the plugin’s featured image</li>
<li><a href="https://github.com/tmconnect" rel="nofollow ugc">Thomas Meyer</a> for the German translation.</li>
</ul>

Easy Featured Images

Allows you to add and remove featured images from admin post lists. Works with AJAX and magic for your image assignment pleasure.

xaraartech

Abuzer

Adds functionality to search images from post page and attach as featured image. 
You will require to create an API key on bing for search API. 
GOTO: https://azure.microsoft.com/en-us/services/cognitive-services/bing-image-search-api/ or https://dev.cognitive.microsoft.com/docs/services/56b43f0ccf5ff8098cef3808/operations/571fab09dbe2d933e891028f 
And generate your “Ocp-Apim-Subscription-Key”

External featured image from bing

Adds functionality to search images from post page and attach as featured image.

Easy Featured Images vs External featured image from bing