I verify here the 'Channels' translation. And here are missing some keys in the german translation.
The most of them I only can see, when I switch to English in the Webseite language.
In German only german keys are on the list.
Helpfull would be a list, where I can see all missing keys in german.
In the attachment you can see the displayed keys for Channels with 'English' and then the Keys in German after Switching to German