High King localisation?

[TMSaxon]

I was curious if it was possible to have certain cultures, for example the First men ones, to have empire level titles localise as High King, rather than simply King of x?
I was also wondering more specifically if it was possible to have them localise to such if they specifically had a king level vassal that had been allowed royal style under them, or any culture for that matter allowing the same in those conditions (it would make sense for the king on top to adopt a superior title, even if it was merely High King - the Anglo Saxons and Irish for example did this)?

 

[Moarice]

If I recall, Clawmen use "High King" as an Emperor-tier title.
Other than that, I think there was some line in the code to give certain cultures their own titles.

 

[TMSaxon]

I was more specifically asking which line of the code where?