If you just use the {Alphabetic} Unicode character class (100K code points), together with a space, hyphen, and maybe comma, that might get you close. It includes diacritics.

I'm curious if anyone can think of any other non-alphabetic characters used in legal names around the world, in other scripts?

I wondered about numbers, but the most famous example of that has been overturned:

"Originally named X Æ A-12, the child (whom they call X) had to have his name officially changed to X Æ A-Xii in order to align with California laws regarding birth certificates."

(Of course I'm not saying you should do this. It is fun to wonder though.)

> I'm curious if anyone can think of any other non-alphabetic characters used in legal names around the world, in other scripts?

Latin characters are NOT allowed in official names for Japanese citizens. It must be written in Japanese characters only.

For foreigners living in Japan it's quite frequent to end up in a situation where their official name in Latin does not pass the validation rules of many forms online. Issues like forbidden characters, or because it's too long since Japanese names (family name + first name) are typically only 4 characters long.

Also, when you get a visa to Japan, you have to bend and disform the pronunciation of your name to make it fit into the (limited) Japanese syllabary.

Funnily, they even had to register a whole new unicode range at some point, because old administrative documents sometimes contains characters that have been deprecated more than a century ago.

https://ccjktype.fonts.adobe.com/2016/11/hentaigana.html

You forgot apostrophe as is common in Irish names like O’Brien.

Apostrophe is common in surnames in parts of the world.

https://en.wikipedia.org/wiki/Perri_6

> I'm curious if anyone can think of any other non-alphabetic characters used in legal names around the world, in other scripts?

Some Japanese names are written with Japanese characters that do not have Unicode codepoints.

(The Unicode consortium claims that these characters are somehow "really" Chinese characters just written in a different font; holders of those names tend to disagree, but somehow the programmer community that would riot if someone suggested that people with ø in their name shouldn't care when it's written as o accepts that kind of thing when it comes to Japanese).

> I'm curious if anyone can think of any other non-alphabetic characters used in legal names around the world, in other scripts?

The Catalan name Gal·la is growing in popularity, with currently 1515 women in the census having it as a first name in Spain with an average age of 10.4 years old: https://ine.es/widgets/nombApell/nombApell.shtml

There’s this individual’s name which involves a clock sound: Nǃxau ǂToma[1]

[1] https://en.m.wikipedia.org/wiki/N%25C7%2583xau_%C7%82Toma

What if one's name is not in alphabetic script? Let's say, "鈴木涼太".

דויד Smith (concatenated) will have an LTR control character in the middle

Comma or apostrophe, like in d'Alembert ?

(And I have 3 in my keyboard, I'm not sure everyone is using the same one.)