The emails are sent when the form is saved so if you put this in your Custom JS:
// Define the variable so it is accessible to the email
var attLink = "";
function dffs_PreSaveAction() {
// Get the attachments
attLink = getFieldValue("Attachments").join("<br>");
return true;
}
Then you use this in your email body:
{var:attLink}
Please note that if you already have a function named dffs_PreSaveAction in your Custom JS you must merge then into one.
Alexander