howdy,
apologies for a verbose Private Message.
I agree,
better regionalizations and translations audio-replacers
would be awesome stuff!
Companies often can't afford to have a dedicated transliteration regionalization department,
let alone the cost of having regionalized voice overs etc...
thats where fans and automating might be a kludge hehe.
so perhaps AGI can be used there... with subcontractor or volunteer transliterators and editors to QualityAssurance check (perhaps from first unit).
Such projects would be excellent potential epistemological and passive-andragogical learning tools...
a one-time cost to intialize, but, with ongoing awesome.
I digress.
at this point post 2015 launch of Fallout 4,
there are likely already regionalization and transliterations for a lot of languages by now,
on Youtube lets-plays, the subtitles.
I think, shavkacagarikia also said there were transcripts/script of Fallout4 was in .rtf...
so, that might be accessible for transliteration.
|.rtf| -> transliteration protocol AGIXML -> |output language font set|
see ThisWeekInTech, ICANN and transliteration for more.
I also shared some ways to have 'screen-reader transliteration'
from some memristive or spintronics-ware producers,
which can be used to transliterate things in real-time, in addition to the subtitles in a game hehe.
this is more universal-translator-y, and more useful for a wider range of languages than just English. 
I hope this was of use for you, and gives you some options,
and that you're able to be playing Fallout4, and customizing in no-time.
perhaps - one day you'll also make your own mods too.