ulfben

This plugin adds an “Use as Featured Image”-action to the Media Library. Very useful if you need to set the post thumbnail / featured image for a lot of posts.
<a href="https://wordpress.org/extend/plugins/bulk-select-featured-image/screenshots/" rel="ugc">A picture says more than a thousand words</a>.
//<a href="https://www.ulfbenjaminsson.com/" rel="nofollow ugc">Ulf Benjaminsson</a> 
Copyright (C) 2012 Ulf Benjaminsson (hello at my full name dot com).
This program is free software; you can redistribute it and/or modify 
it under the terms of the GNU General Public License as published by 
the Free Software Foundation; either version 2 of the License, or 
(at your option) any later version.
This program is distributed in the hope that it will be useful, 
but WITHOUT ANY WARRANTY; without even the implied warranty of 
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 
GNU General Public License for more details.
You should have received a copy of the GNU General Public License 
along with this program; if not, write to the Free Software 
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

Bulk-Select Featured Image

Allows you to select Featured Image / post thumbnail for your posts directly from the media library view.

wphigh

Admin Featured Thumbnail WordPress plugin can Add featured image thumbnail to WordPress admin columns. It will help you easy to know which post is attached the featured image. Add click the thumbnail will popup preview the full image.
It also support custom posts.
<a href="http://www.wphigh.com/portfolio/admin-featured-thumbnail-wordpress-plugin" rel="nofollow ugc">Feedback Admin Featured Thumbnail</a>

Admin Featured Thumbnail

Add post thumbnails to admin list of posts.

Bulk-Select Featured Image vs Admin Featured Thumbnail