Ok, I exported the Swedish language file for the plugin User Activity.
Both, po and mo files.
Uploaded to Plugins: /wp-content/languages/plugins/textdomain-locale.mo as per manual.
I also uploaded to plugins language folder like it says in the manual too: "You can just drop it in the plugin’s languages folder."
Still, it does not show up in Swedish.
I have logged out and in again. Tried to refresh browser etc.
Am I missing something simple here ?