Using this snippet, you can bypass Elementor's maintenance mode by adding ?bypass_maintenance=1 to the query string

bypass-elementors-maintenance-mode.php

<?php

add_filter( 'pre_option_elementor_maintenance_mode_mode', function ( $option ) {

	$parameter = 'bypass_maintenance'; // change this to whatever you like

	if ( isset( $_GET['bypass_maintenance'] ) and $_GET['bypass_maintenance'] ) {
		return 0; // needs to be falsy but not FALSE
	}

	return $option;
} );