Hi,
The medias metadata can be modified through the metadata manager. However, it is not possible to apply the same modification to several files.
For example, right now, If I want to add the genre "Rock" to all my Lou Reed's albums, I have to do so for each album, one by one. Emby does have a multiselection tool to do basic operations such as "deletion" or "content update", but it cannot be used with the metadata manager.
Thanks