As reported by dinism in in MDL-78509:

There are some strings hardcoded to english:

Cancel login

<form id="cancelmfa" method="POST" action="{authurl}">
            <input type="hidden" id="uniqid-logout" name="logout" value="true">
            <input type="submit" class="btn btn-secondary"
                   name="cancelmfa" id="cancelmfa_button"
                   value="Cancel login" data-initial-value="Cancel login">

</form>

https://github.com/moodle/moodle/blob/9890e67e6d262a0a5eb938bc3b007045fe067ec9/admin/tool/mfa/templates/verification_form.mustache#L88

Need help

<div class="tool-mfa-site-support mt-4">
        Need help? {supportlink}
    </div>

https://github.com/moodle/moodle/blob/9890e67e6d262a0a5eb938bc3b007045fe067ec9/admin/tool/mfa/templates/verification_form.mustache#L93