matroska's video container allows for tags (title, author, description, copyright, etc). is there a way to display this info in dopus?
Opus can play MKV movies but it doesn't have any built-in support for their metadata.
Unless someone writes a plugin I think the only way it could currently be displayed is if you have a shell extensions which adds additional columns to Explorer and Opus for the fields. Those columns would appear under the "Special" columns category in Opus's folder options window if they exist.