Custom queries for Elementor use - WordPress. To be inserted in you theme's functions.php or a custom made functions plugin.

custom_elementor_queries.php

<php
/* 
*	Custom queries for Elementor
*       by ellegaard ID
*/

/*  Get direct children of current page 
*
*	for query ID use 'pages_direct_child_filter'
*/
     
add_action( 'elementor/query/pages_direct_child_filter', function( $query ) {
	// Get current page
	$current_page = get_queried_object_id();
	// Modify the query
	$query->set( 'post_parent', $current_page );
} );
	
/*
*	Get siblings of current page
*
*	for query ID use 'pages_siblings_filter'
*/
add_action( 'elementor/query/pages_siblings_filter', function( $query ) {
	//get parent ID
	$id = wp_get_post_parent_id( get_the_ID() );
	//modify query
	$query->set( 'post_parent', $id );
} );
	
/*
*	Getting same costum taxonomy of current page
*
*	for query ID use 'pages_same_cpt_cat_filter'
*/ 
add_action( 'elementor/query/pages_same_cpt_cat_filter', function( $query ) {
	// get ID of current page
	$id = get_queried_object_id();
	// tax terms of chosen taxonomy - insert instead of 'custom_taxonomy_name' 
	$tax = get_the_terms( $id, 'custom_taxonomy_name');
	// choose slug as field
	$query->set( 'field', 'slug');
	// get slug of current tax
	$query->set( 'tax_query', $tax[0]->slug );

} );