Magento 2 Infinite AJAX Scroll - Cyno Infotech
https://www.cynoinfotech.com/product/infinite-scroll-magento-2-extension/
Magento 2 Infinite Scroll is a feature that provides new functions that give admin more choices in setting up how to load the next pages: supports loading product list infinitely by Cynoinfotech Scroll in Magento 2 when customers scroll down to the end of pages, free to customize Load More button/ Back to Top button, lazy loading image. Magento 2 infinite scroll allows products to load automatically without loading the entire page, while pagination splits content into separate pages.