In Elementor Pro, the post widget has the option of setting a custom query filter

Then I can add code in my functions.php to retrieve whatever posts/pages/taxonomies specified in my custom query. In my case, this is what I use:

/** the elementor/query/ part of the add_action is always present. The next part is the name of my custom query filter, as provided in the Query ID (screen dump) and then the function where I set the query using native WP query.

add_action( 'elementor/query/park_related_by_taxonomy', 'pixlweb_related_posts' );

function pixlweb_related_posts( $query ) {

$post = get_queried_object();

$post_tags = get_the_tags($post->ID);

$t = array();

foreach($post_tags as $tags){

$t[] = $tags->name;

}

$params = array(

'post_type' => 'parkexperience',

'tax_query' => array(

array(

'taxonomy' => 'post_tag',

'field' => 'slug',

'terms' => $t,

),

),

);

$query->set( 'tax_query', $params );

}