Bart Kuijper

When displaying a post or comment with avatars enabled, WordPress will always check for the existence of a Gravatar. (Note: even the default avatars ‘mystery person’ and ‘blank’ are in fact Gravatars served from gravatar.com.) WordPress does this by sending an MD5 hash of every displayed post or comment author’s email address to gravatar.com. Even with many plugins that introduce locally stored default or user avatars, this check still happens. On top of that, some themes or plugins force (Gr)avatars to load even if the display of avatars is disabled completely in WordPress’ settings. If for whatever reason you do not wish for Gravatar to receive these requests (which some people have voiced GDPR concerns about), this plugin is for you.
The way it works is every time WordPress attempts to display an avatar, this plugin first checks if the image is about to be retrieved from gravatar.com. If it is, the URL is changed to the locally stored ‘mystery person’ image (included with this plugin). If the avatar has any other source, this plugin doesn’t interfere.
Gravatars are also removed from the Discussion page in Settings and replaced with the locally stored ‘mystery person’ image. Again, any non-Gravatar images are left alone.
Upon activation of this plugin, if a Gravatar is selected as the default avatar, that setting is changed to the locally stored ‘mystery person’ image. If any non-Gravatar avatar is selected, that setting isn’t changed.
Upon deactivation of this plugin, if the locally stored ‘mystery person’ image is selected as the default avatar, that setting is changed to the Gravatar logo. If any non-Gravatar avatar is selected, that setting isn’t changed.

Redirect Gravatar requests

All requests to load an avatar from gravatar.com are redirected to a local image, preventing Gravatar from potentially gathering data about your site  …

Maruti Mohanty

As the name suggests, this plugin allows you to use the social profile picture as your WordPress Avatar. 
You can see more, on how to install and use the plugin here in this blog <a href="http://www.sourcexpress.com/wp-social-avatar/" rel="nofollow ugc">WP Social Avatar</a>
Why this plugin?
If you are me, who gets bore of using the same gravatar for few days or months then this plugin is totally for you. 
This plugin provides option to the user to use Social media like Facebook and Google plus profile pictures as the gravatar instead of the one from en.gravatar.com.
WP Social Avatar Settings:
After activating the plugin admin will see WP Avatar, under Users menu. Here the admin can set the minimum role/capabilities required to avail this feature.
The allowed users will see the available options in their Your Profile sub menu under Users menu.
For the first version I only have two social options available, Facebook and Google plus. You need to add either the Facebook user ID(numeric) or Google plus id in the corresponding fields. <a href="http://findmyfacebookid.com/" rel="nofollow ugc">You can find your facebook user id here</a>
Once done with the above, check the social profile picture you want to use as the gravatar and click Update Profile and you are done.
After saving the profile you can see all the gravatars in the site has been replaced by the respective social media profile picture.
With this you will get rid of the boredom of looking at the same gravatar all the time. With the change in the respective social media profile picture, the gravatar of your site will also change.
With Version 1.4 Cache functionality is implemented for Google Plus avatar, this optimizes the functionality. I have added a clear cache button for Google plus, anytime you upload a new profile picture in your Google Plus account click the “clear cache” button and you will get the latest image else the code will make a request and pull the latest image after every 48 hours. This has been done to make the Google Plus functionality faster.

WP Social Avatar

This plugin gives the users the option to use their social profile picture as the WordPress Avatar

Redirect Gravatar requests vs WP Social Avatar