The console uses a secondary language
The secondary language (Settings > Configure Plasma translations
| $ echo $LANGUAGE >> en_US:cs
) is applied to the console. English is expected.
(Have a look at QMLKonsole issue, but it's not just a matter of QMLKonsole. The same appears in ssh
after use $ export $(cat /proc/$(pidof plasmashell)/environ | tr '\0' '\n')
)