add_filter( 'wpex_main_metaboxes_post_types', function( $types ) {
// Add to my custom-type post type
$types[] = 'custom-type';
$types[] = 'custom-type-2';
$types[] = 'custom-type-3';
// Remove from blog posts
unset( $types['post'] );
// Return post types array
return $types;
}, 20 );