The equations created with the new equation editors are read by screen readers.
Formulas with MathType are delivered as images using an <img> HTML tag. The way to provide accessibility to an image is to add proper text to the ALT attribute. Such text is automatically generated when you create the formula, and no human intervention is needed.
The text associated with a formula in the ALT attribute resembles natural language as much as possible. Thus, all mathematical symbols are also expressed in its textual form.
For detailed information on Accessibility for the Math editor, please see https://docs.wiris.com/en/mathtype/mathtype_web/accessibility?s[]=accessibility