Justin, I think you’ll need to make a separate metadata preset for FLAC since it’s not In the metadata window you show. The FLAC metadata window should be available when you select to make a FLAC file. I guess FLAC and Ogg Vorbis use Vorbis Comments, so such a preset should be good for both. (another one outside the “normal” metadata window would be Windows Media Audio files using WMA).
I believe this shows standard mappings for the different metadata types:
http://wiki.hydrogenaud.io/index.php?title=Tag_Mapping
In addition to ID3 and the others, the tables cover RIFF INFO too.