Its an interesting idea, but I wonder if such cards wouldn't stand out once the idea became well known? Allowing a new name to be used is good, but immediately following it with the initials of the former name seems awkward. But, then, I am not familiar with Swedish names. How many persons have ID cards which include First Name, two middle initials, Last Name?
Offering the use of puberty blockers, however, would be profoundly humane.