Bilal Akil

I was creating link posts on http://www.bilalakil.me’s Twenty Fourteen happily 
until I was nonplussed by the doppelgängers that made themselves apparent 
when I added the theme’s also-impressive Euphoria widget to the mix, displaying links.
I was seeing the same posts displayed twice on the front page: 
once in the main post loop; and again in the Euphoria widget!
To solve this problem I decided to exclude posts with the link post format 
from the post index page’s main query, 
and thus this plugin was born.
The plugin’s settings sit neatly on the Settings > Reading page.
You can find this plugin at: https://bitbucket.org/bilalakil/formataway

Formataway

Formataway lets you exclude selected post formats from your post index page's main query.

Eduardo Zulian

The Post Format Gallery Widget plugin creates the possibility for you to display images from your galleries inside posts saved under the format ‘Gallery’. You can select the number of images to display, the size of these images, shuffle their orders, the target of links (image file, permalink to attachment, permalink to post or maybe no linking), show captions and use one copy of the basic WordPress style for galleries, which will allow you to set up easily a number of columns.
Important: your theme must support the <a href="https://codex.wordpress.org/Post_Formats#Adding_Theme_Support" rel="nofollow ugc">Gallery post format</a>, otherwise it won’t work.

Post Format Gallery Widget

Display in a widget images from your galleries saved under the post format Gallery.

Formataway vs Post Format Gallery Widget