stigcq

A plugin offering a widget showing recent photos in posts. It can be configured 
as for how many photos to show, the title on the widget and max width and height for 
thumbnails.
The thumbnails links to the post where the photo is showing. They show a mouse over 
effect with bigger version of the photo in a tooptip.
It has option to exclude photos from the view.
It has only been tested with WP 4.2, it might work with lower versions.

Recent photos widget

A simple widget which shows thumbnails of latest photos in posts

Heavy Heavy

Erik Ford

With Flickr Me, you can add Flickr feeds, from an individual account or group, to your widget ready areas. Once installed and activated the widget is an easy to manage, out of box solution for displaying a Flickr gallery of images. Each photo, in the feed, will link to its Flickr permalink and you can optionally set to display the title when stacking images.

Flickr Me

Add Flickr feeds to your widget ready areas.

Recent photos widget vs Flickr Me