Way to add hover overlay on images to signify clickability?

I have 4 graphics on my front page that are clickable. However one does not see that at a glance. Some images are NOT clickable. Is there a way to display a hover overlay in a subtle yellow on those images that are clickable?

The pictures in question are the “Ö3 Podcast award” and the 1/3 profile pictures and the speed learning starter guide picture.
The idea is to show that they are clickalbe when you hover over it. Much like when you hover over the buttons.

Appreciate your help

Hi Florian,

Thank you for reaching out to us. I am happy to help with your queries.

Can you share a screenshot to point me the exact location needing help with?

aThemes Support

Sure. If you scroll down you will see it. I have made it smaller so you can see all the images in one picture.
They are pictures added via the picture widget that lead to a page. Only those marked red lead somewhere (are clickable) the others are (currently) not leading anywhere.
It would be nice to have a way of displaying a hover effect like that over each image that leads to a page.

Thanks so much for your help!