Nofollow

Sorry, you can’t. At least it’s not that easy.

You would have to use the direct PHP approach (https://www.ads-software.com/plugins/related-youtube-videos/other_notes/) and, for example, code this directly into your tempalte file(s).

In version 2 [which, if I’m honest, don’t know when it’s coming out. Maybe earlier next year?] you will be able to create your own HTML templates.