Hello stcelestine,
Thanks for messaging us.
By default there is no option to change it fade, you need to customize the theme itself. It will take much time to customize it. The file you need to change is assests/js/education-base-custom.js , the slider hook is in the file acmethemes/hooks/slider-selection.php.
We have similar theme but it have fade slider, maybe you like it
Best Regards!
Acme Themes