Hi Andy,
No, Scrivener doesn’t support this, and there are no plans to add it in the near future, either. There are both legal and technical issues here:
Legal: In order to embed a font in an .epub, you (the end user) must own the necessary rights to use that font. This is a bit of a fuzzy area. Fonts can be embedded in certain documents - PDF documents and .docx documents, for instance - but it would take a lot of reverse-engineering to get them out again. But an .epub file is just a .zip file, so anyone could just unzip the file and get the fonts - thus this could be considered distribution and not be covered by standard licences. The .epub 3.0 format (and Adobe) supports font obfuscation, but not all readers do yet and this gets a little complicated. It’s much better to avoid this altogether and to use only fonts with open licences (but it would be up to the end-user to ensure this), which leads on to technical issues.
Technical: the .epub spec generally requires OpenType (.otf) fonts, but the Mac uses many different font types - .otf, .ttf, .ttc and so on (just take a look in your /Library/Fonts directory). So only a subset of the fonts on your system would be available for embedding. Thus Scrivener would not be able to present you with the standard Fonts panel (which shows you all fonts on the system) and would instead, for .epub format, have to search for all .otf fonts on your system somehow and only present you with those. But again, it would have to rely on you ensuring that you have the necessary rights to embed these fonts in your e-books.
Given the above (along with the headache it would be to implement this!), I tend to think that it’s much better to avoid font embedding and leave this to the professional publishers, who have legal teams and access to font libraries.
You can read more about font embedding here, though:
blog.threepress.org/2009/09/16/h … pub-files/
All the best,
Keith