In the US there are two was of doing name change, by court which is very simple and does not require (when I looked into it) a lawyer, a paralegal could easily do it, or even someone versed in the method. The other way is by usage, it involves a notarized form, and then changing every document/ etc into the new name. The usage method, though, cannot change the passport name for 5 years. At least that’s the way it was in 1992.
Interesting, thanks.