At AgentFire, we help our clients by optimizing our core templates to be within ADA compliance standards. All websites are compliant out of the box, and our designers will suggest best practices and warn you of any non compliant requests during the initial development phase.
However, because we allow for client controlled design and content, it is ultimately the client's liability to continue to maintain and ensure their website stays ADA Compliant.
If you are interested in an extra layer of security, we recommend looking it ADA Protect addon, available from Marketplace section of your website. Note that this addon does not make your website automatically compliant.
For your site to be ADA compliant, it should meet a number of requirements. You can find the ADA compliance checklist for websites here https://siteimprove.com/en-us/accessibility/ada-compliance-website/ or here https://mayecreate.com/blog/what-does-ada-compliant-mean/
As you can see, many site elements can’t be controlled by the plugin, like alt tags for images, caption, content structure etc.
Follow the guidelines after updating your website content to keep it in compliance.