We'll create fresh WordPress site with Tags for Media Library installed. You have 20 minutes to test the plugin after that site we'll be deleted.
TML – Tags for Media Library may be useful to anyone trying to use taxonomy tags on WordPress Media Library items. TML supports dynamically generating galleries using a criteria based on taxonomy tags, multiple tag taxonomies for media items, bulk assignment/removal of taxonomy tags to/from media items, filtering the Media Library by taxonomy tags, sorting the media items based on a priority tag, a search widget for media items using a criteria based on taxonomy tags and an alternate high density view of the Media Library. The website for this plugin is here. This version requires WordPress 4.6 and PHP 5.4.
TML also includes a gallery viewer. TML’s gallery viewer is a plug compatible replacement for the standard WordPress gallery viewer for the WordPress [gallery] shortcode. It can be used independently of the other features of TML and supports five different views of a gallery.
For NextGEN Gallery 1.9 users: This plugin first converts NextGEN Gallery’s image database to a WordPress Media Library image database. After the conversion NextGEN Gallery images and galleries have become WordPress Media Library images and galleries. A WordPress taxonomy ‘ngg_tag’ is created and the NextGEN Gallery image tags are saved in this taxonomy. This plugin implements the NextGEN Gallery shortcodes [nggtags], [nggallery], [slideshow], [album] and [singlepic] by dynamically translating them into an equivalent standard WordPress [gallery] shortcode so post content with these shortcodes will still work without editing the post content. NextGEN Gallery’s sortorder is implemented using a tag taxonomy to hold priorities. This plugin works with NextGEN Gallery 1.9.13.