By default, Criipto Verify uses the Accept-Language HTTP request header to figure out which language the user prefers.
You can override this per authentication request by specifying a
ui_locales query parameter. This works for both OpenID Connect and WS-Federation, even if WS-Federation does not have protocol support for per-request language selection.
The actual support for controlling the language varies by e-ID method
en. Keyfile is only available in danish.