Thanks for the link as I see why I didn’t see a hover state on my end (I had the text over the image, not underneath). However, I did see the button there does add a slight hover but it can’t be customized.
I did a video a while back that you could try if you feel comfortable with CSS, you can try this with .gallery-section in my case being what I used for my section with the gallery.
.gallery-section [data-hook=“custom-button-button”]:hover,
.gallery-section [data-hook=“custom-button-button”] .button__label:hover{
background-color: coral !important;
color: purple !important;
}

It could probably use some optimizing and you can customize the colors as you see fit but I hope this can help.