Yes, it is possible with a small modification and a custom code. Follow the steps below, I will try to guide you. If you need help with editing the files, you can fill the ticket details with FTP access, and I will do it for you.
1. Open up the wp-content\plugins\related-posts-pro\includes\related_content.class.php file on your server and change line 1514 from this:
$this->post[$key] = apply_filters('rpp_item_after_postprocessing', $post);
$this->posts[$key] = apply_filters('rpp_item_after_postprocessing', $this->posts[$key]);
2. Then add this code snippet to the functions.php file in your active theme directory (copy from line 4):
3. Open the plugin settings and save them without changing anything, so the cache will be cleared.
The titles should appear trimmed now.Best,
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