Yasar Khalifa

Default Alt Text is a lightweight SEO Plugin that helps improve your site’s SEO and accessibility by ensuring every image always has an alt attribute. If an image in the Media Library doesn’t have an alt text set, this plugin will automatically use the image’s title instead, on the front-end only,so your database remains untouched.
This is especially useful for sites with lots of images uploaded without alt text, helping you maintain better SEO and a more accessible site without editing each image manually.
<h4>Features</h4>
<ul>
<li>Displays default alt text if none is set</li>
<li>Uses the image title as fallback alt text</li>
<li>Does not modify Media Library data</li>
<li>Improves SEO and accessibility</li>
<li>Lightweight and simple,no settings needed</li>
</ul>

Default Alt Text | SEO Plugin

Displays a default alt text for images on your site when none is set — simple, fast, and great for SEO.

Farhad Sakhaei

ParsMizban

DediData

This plugin optimizes WordPress for better ranking in Google and other Search Engines 
* Add post excerpt as Meta Description
Validated by: 
https://wpreadme.com 
https://wordpress.org/plugins/developers/readme-validator

Smart SEO

Smart SEO - WordPress Search Engine Optimization Tools

Default Alt Text | SEO Plugin vs Smart SEO