Users do not scroll through images in the slideshow. If something is hidden, it's not there. Of course, users don't have time to wait for an animated slideshow to change frames. So slideshows are simply ignored in real life, especially if it's a Hero or Header element. The user scrolls down the page looking for what they want, especially on mobile.
So the best solution is to expand the slideshow into image and caption blocks. This way, users will always see what's hidden inside. Especially if inside the slides are not just pictures, but real content, such as special offers or products and services. You don't have to hide it all from the user.
There are cases where a slideshow makes sense, for example, it is an acceptable pattern when displaying images on a product page.
In this case, it is better to show slide thumbnails to navigate through the slideshow. This is a convenient and obvious interface. Dots navigation should always be avoided. Although this is a frequently used pattern, most users don't see dots as navigation.
And of course, we should not forget that on mobile slideshow's navigation should work by swiping photos left and right with touch. Although, to be honest, this is an absolutely useless thing on mobile slideshows. Have you ever swiped through a slideshow on your mobile? Hardly anyone does it at all.
So on mobile, the best solution would be to turn the slideshow into a vertical feed of images so that they're accessible with a normal down-scroll.