I wonder if you could circumvent some of this with the default first/given & last/family name with two checkboxes to choose the preferred name to be called with. Of course it wouldn't be bullet-proof if you wanted to substring the name, like using only the 2nd part in Vietnamese names, and you probably would have to make filling both of them optional.

Or just having a preferred name and full name, duplicating data but probably it wouldn't be a big deal in most cases.

This would be a nice GitHub project for someone to showcase name inputs in all languages.