Add the sample code below to your child theme's functions.php file or in a site specific plugin.
<?php
//* Do NOT include the opening php tag
//* Remove Jetpack related posts on single event pages
function ee_jetpackme_no_related_posts( $options ) {
if ( 'espresso_events' == get_post_type() && is_singular() && !post_password_required() ) {
$options['enabled'] = false;
}
return $options;
}
add_filter( 'jetpack_relatedposts_filter_options', 'ee_jetpackme_no_related_posts' );
References:
https://eventespresso.com/topic/hiding-related-posts/