most popular by custom field value

On page refresh +1 value is added to a custom field of each post:

on functions.php:

function wpb_set_post_views($postID) {
    $count_key = 'wpb_post_views_count';
    $count = get_post_meta($postID, $count_key, true);
    if($count==''){
        $count = 0;
        delete_post_meta($postID, $count_key);
        add_post_meta($postID, $count_key, '0');
    }else{
        $count++;
        update_post_meta($postID, $count_key, $count);
    }
}
remove_action( 'wp_head', 'adjacent_posts_rel_link_wp_head', 10, 0);

on posts:

wpb_set_post_views(get_the_ID());

now how i can get the most popular of one category by combine the flexible posts widget & this costum field?

https://wordpress.org/plugins/flexible-posts-widget/