Searching at Cssremix.com

whenever you hover on the item you can observe the "Sights" function I am presuming they're utilizing a wordpress plugin that links using the publish sights however when clicked on the product redirects to not the publish but to some website/site used

This plugin provides you with the publish sights. To filter a hyperlink you are able to hook into certain filters, for example post_link or the_permalink.

Here are a few paperwork:

The usage could be something similar to this:

add_action('post_link', 'do_custom_link');

function do_custom_link($url, $post) {
  $external_url = get_post_meta($post->ID, 'external_url', true);
  if($external_url) {
    return $external_url;
  }

  return $url;
}

This could obtain the exterior url from the meta field stored with the post, known as external_url. You'd define that meta area while using custom fields UI whenever you produce the publish with the admin pages.