For sure.
Follow these steps:
1. In WP Show Posts create a new List, and name it related
1.1 Set the Post Type to Post and Posts per page to the number of posts you want to display eg. 4
.
1.2 DO NOT set a taxonomy.
1.3 Set the Columns, Images, Content as you would do any other list.
1.4 Publish that.
2. Now create a new Hook Element in Appearance > Elements.
2.1 Add this PHP to the Element:
<div class="wpsp-related-posts grid-container">
<h2>Related Posts</h2>
<?php
if ( is_single() ) {
$cats = get_the_category();
$cat = $cats[0];
} else {
$cat = get_category( get_query_var( 'cat' ) );
}
$cat_slug = $cat->slug;
$list = get_page_by_title( 'related', 'OBJECT', 'wp_show_posts' );
wpsp_display( $list->ID, 'tax_term="' . $cat_slug . '"' );
?>
</div>
2.2 Set the Hook to where you want it displayed eg. generate_after_content
2.3 Check Execute PHP
2.4 Set the Display Rules to Posts > All Posts