There are no fully accessible GUI math widgets. The closest is probably PhET https://phet.colorado.edu/en/accessibility. Sadly most people just say some text description is equivalent, which it is not. You should think about which accessibilities you want to provide, color adjustments, contrast settings, dark mode, screen reader compatibility, captions, keyboard control, mouse control, simplified text, ... then look for a widget and evaluate which are not supported. Just communicate with everyone so expectations are clear. Here is a report and app I wrote many years ago http://diagramcenter.org/accessible-dynamic-scientific-graphics.html