If I understand you correctly, then you only want to change the text of the mail. This you can do via the filter hook password_change_email
. No need to redeclare the function, which you actually can’t do. Below you find an example on how to use the password_change_email
filter to change your message text.
add_filter(
'password_change_email',
'wpse207879_change_password_mail_message',
10,
3
);
function wpse207879_change_password_mail_message(
$pass_change_mail,
$user,
$userdata
) {
$new_message_txt = __( 'Some text ###USERNAME### more text
even more text ###EMAIL### more text after more text
last bit of text ###SITENAME###' );
$pass_change_mail[ 'message' ] = $new_message_txt;
return $pass_change_mail;
}
I’ve tested this and it works. Just to clarify, this applies to the use case, in which one changes and updates the password via the backend user management.