UsableNet

Enable is a web accessibility plugin developed by uPress, designed to improve website accessibility for users with various disabilities. It offers a range of features aimed at enhancing the user experience, such as text-to-speech functionality, keyboard navigation support, and color contrast adjustments. Enable is particularly tailored for WordPress websites, integrating seamlessly with the popular content management system. While it provides a quick way to address some accessibility issues, website owners should consider it as part of a broader accessibility strategy rather than a complete solution for full compliance with accessibility standards.

Accessibly is an app which is designed to assist with meeting certain requirements of WCAG 2.1 using an overlay solution.

NagishLi is a free accessibility plugin from Localize*, created to provide an equal oppurtunity for webmasters to make their website accessible and make the internet more accessible for people with disability.

AdaSiteCompliance is a web accessibility solution, making websites compliant and accessible to WCAG 2.1 and section 508 compliance standards.

Pojo.me provides a specialized accessibility overlay plugin designed to work seamlessly with any WordPress theme or page builder. This tool aims to enhance website accessibility without requiring extensive modifications to the existing site structure. Pojo.me's solution includes features like keyboard navigation support, text-to-speech functionality, and customizable color and contrast options. While it's marketed as a quick solution for improving accessibility, it's important to remember that comprehensive accessibility often requires a more holistic approach beyond just using an overlay.