You could use my Show Posts plugin: https://wordpress.org/plugins/wp-show-posts/
However, that won’t convert your category pages, it will just allow you to create new pages that update with the category posts automatically.
Otherwise you’ll need to find another plugin, or mess around with some CSS:
.category .post .inside-article > *:not(.post-image) {
display: none;
}
@media (min-width: 769px) {
.category .type-post {
width: 33%;
float: left;
}
.category .paging-navigation {
clear: both;
}
}
Hope this helps ๐