create a shortcode with acf including a filter

This is not the full working code, just to illustrate how to add the shortcode and trigger the function.

<?php

   // Check if ACF is available
   if(function_exists('get_field')) {
       function modell_nach_personenzahl_variabel() {
           $args = array(
               'post_type'   => 'womos',
               'order'       => 'ASC',
               'orderby'     => 'personen',
               'field'    => $atts['personen'],
               'numberposts' => -1,
               'meta_query' => array (
                array (
                    'key' => 'personen',
                    'value' => '6'
                )
            )
        );

        $query = new WP_Query($args);

        if($query->have_posts()):
            while($query->have_posts()):

             // for testing purposes
             echo "<pre>";
                print_r($query->the_post);
             echo "</pre>";

             ?>
                <h1><?php the_title(); ?></h1>
                <!-- get the rest of the fields -->

            <?php
            endwhile;

        endif;

       // Add the shortcode
       add_shortcode('filter-camper-nach-personen', 'modell_nach_personenzahl_variabel');
   }