natekinkead

When you upload a new image in WordPress, this plugin will use the file name to automatically fill in the Title, Alt text, Caption fields, and Description so you don’t have to do it manually.

Image Automatic Alt Text and Caption

Automatically fills in the Alt text, Caption, and Description from the image file name of new image uploads.

litefeel

Comments Avatar Lazyload at server side load replace the src property of img tag. It is relly lazyload. It was successfully checked by W3C. 
It is only lazyload comments avatar.
Related Links:
<ul>
<li><a href="https://www.litefeel.com/comments-avatar-lazyload/" title="Comments Avatar Lazyload Plugin for WordPress" rel="nofollow ugc">Plugin Homepage</a></li>
<li><a href="https://www.litefeel.com/" title="Author For Comments Avatar Lazyload Plugin" rel="nofollow ugc">Author Homepage</a></li>
<li><a href="https://github.com/lite3/comments-avatar-lazyload" title="On GitHub" rel="nofollow ugc">On GitHub</a></li>
</ul>

Comments Avatar Lazyload

Comments Avatar Lazyload at server side load replace the src property of img tag. It is relly lazyload. It was successfully checked by W3C.

Image Automatic Alt Text and Caption vs Comments Avatar Lazyload