Autoplay Quote block

That solution doesn't flatten the text into an image, it turns the section into a slide that allows them to rotate through, it still includes text.

A different solution would be to use a list section and add different plugin to allow them to auto scroll:

https://www.will-myers.com/articles/auto-scroll-for-carousel-banner-slideshows-for-auto-layout-sections-in-squarespace-71

(but this doesn't use the quote block as you requested)