WPU Import Export is a wonderful plugin.
add_filter( 'wpu_import_export_post_types', function( $post_types ) {
$post_types['event'] = [
'post_type' => 'event',
'unique_key' => 'uniqid',
'columns' => [
'title' => [
'type' => 'post_title'
],
],
];
return $post_types;
} );