The swipebox plugin is this https://www.ads-software.com/plugins/easy-swipebox/
I use a repeater field with ACF to create the gallery
The code I use is this
<?php if ( have_rows( 'elenco_video' ) ) :?>
<div class="grid elenco_video">
<?php $video = 1; ?>
<?php while ( have_rows( 'elenco_video' ) ) : the_row(); ?>
<div class="col-33 tab-50 sma-100 item">
<?php
//second false skip ACF pre-processcing
$url = get_sub_field('embed_video', false, false);
//get wp_oEmed object, not a public method. new WP_oEmbed() would also be possible
$oembed = _wp_oembed_get_object();
//get provider
$provider = $oembed->get_provider($url);
//fetch oembed data as an object
$oembed_data = $oembed->fetch( $provider, $url );
$thumbnail = $oembed_data->thumbnail_url;
$iframe = $oembed_data->html;
?>
<a href="<?php echo $url;?>" rel="group-<?php echo $video;?>"><img src="<?php echo $thumbnail;?>" alt="" /><svg class="icon icon-youtube"><use xlink:href="#icon-youtube"></use></svg></a>
</div>
<?php $video++; endwhile; ?>
</div>
<?php endif; ?>