You're going to need to be more specific about your use case and about what you expect to happen here.
Linking to a #hash anchor (presumably you mean on the same page, not on another page on the same site) is technically internal, not direct, traffic. But:
[a] I don't see how this would affect your reporting, since the Original Referrer would already be set from the initial pageview
[b] by default, Marketo doesn't track links with hrefs that start with #
Thanks, the problem was that the client included the onpage anchor link with the language path folder in front of it so Marketo thought this would be a new page and replaced the referrer.