Hi Mats,
I suggest you work with a web developer for this, we do not support WooCommerce for Flexform. We of course do in our newer WooCommerce themes, where something like this would be done from with the page builder.
You can request the customsiation here: http://www.swiftideas.com/customization/ and our partner WerkPress could hep you.
Broadly speaking, you could also create a new WP page template and utilise a new WP Query to loop through a product category.
<?php
$args = array(
'post_type' => 'product',
'posts_per_page' => 1,
'product_cat' => 'category-name',
);
$loop = new WP_Query( $args );
while ( $loop->have_posts() ) : $loop->the_post(); global $product; ?>
<li class="">
<h3><?php the_title(); ?></h3>
</li>
<?php endwhile; ?>
<?php wp_reset_query(); ?>