Here are some tools to use with Figma for accessibility.
A11Y color contrast checker (Free)
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Ensure your text is readable for users by adhering to WCAG (Web Content Accessibility Guidelines) standards.
This plugin checks the color contrast ratio of all visible text in a frame and provides feedback on whether it meets WCAG’s AA and/or AAA level compliance. It also provides color sliders that allow users to adjust the colors and understand how the corresponding contrast ratio changes in real time.
Stark Accessibility Tools (paid)
With tools like Contrast Checker, Focus Order, Alt-Text Annotations, Vision Simulator, and more all in one place, you can find accessibility issues in a design before it goes into production—or quickly analyze and fix what’s already in flight. Get started for free today!
Color Blind
You can use the color blind plugin to get an accurate and real-time simulation of your designs based on the type of disorder you have selected.
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https://www.figma.com/community/collections/plugins-accessibility
Please check the link to see more Figma plugins for accessibility.