In most of your desktop clients and Windows apps the Check Accessibility is translated into "Kontrollér hjælp til handicappede" and the new group Accessibility in the ribbon is translated into "Hjælp til handicappede"
In the online versions this is translated into "Kontrollér tilgængelighed" in the "Tilgængelighed" group which is much, much better.
It is also kind of inconsistent within the clients since the Accessibility Checker pane is translated into "Tilgængelighedskontrol" but the text in the pane says "Der er ikke fundet problemer i forbindelse med hjælp til handicappede. Personer med ..." which just should be translated into "Der er ikke fundet problemer med dette dokuments tilgængelighed. Personer med ..."
This is also valid for the Filer > Oplysninger > Kontrollér, om der er problemer > Kontrollér hjælp til handicappede command.