From peeking at this code, it looks like this now depends on the configured name layout. (JIRA isnāt loading for me, so I canāt find the ticket for this.)
The key you would need to translate is whatās in ānameMappingsā for the name layout you have enabled.
As @lluismf said, the labels come from the message.properties file, if a name layout is in use, you might want to look at the layout in use to know the actual code that you will need to translate in the message.properties file