Use venues for related events instead of categories

related-events-venues.php

/*
* The Events Calendar snippet
* Modify related events query arguments to use venues
* Gist: https://gist.github.com/jentheo/2f7c7fc0d27353db812f6ea8e4c35778
*/
add_filter( 'tribe_related_posts_args', 'tribe_modify_related_posts_args' );
function tribe_modify_related_posts_args ( $args ) {
	$venue_id = tribe_get_venue_id();
	
	if ( $venue_id ) {
		unset( $args['tax_query'] );
		$args['meta_query'] = array(
			'relation' => 'AND',
			array(
				'key' => '_EventVenueID',
				'value' => $venue_id,
				'compare' => '=',
			)
		);
	}

	return $args;
}