Idea was great to hear native (or mostly navite in some examples like Savoy or Courland ect..) language when we play it. But some people cannot hold to hear in german "sir", or english when play Louisiana. So here are quick steps to solve it.
#1 First we must have .pack editor. Download for example here: Pack File Manager
#2 Open by toy from step #1 main.pack file from data directory in your empire folder. For example: C:\Program Files\Steam\SteamApps\common\empire total war\data
(here can be different file due to mods or clean instalation. If u use Vanila skip to #3 step. If u using a mod for example Imperial Splendour you must edit "Imperial Splendour.pack" file. I think in other mods also their .pack files, or maybe main.pack will be enough to edit. I don't test it.
#3 Go to faction tables inside file following that tree: db / faction_tables / factions
#4 Then pick nation are you interesting in and go to the column called "Abrevation" That is 5 from end. And edit it due to shortcuts below.
There are now 17 languages default in game:
Ar - Arabic...
Cz - Czech... but what he doing in E:TW
Du - Dutch
Fr - French
Ge - German
Hi - Hindu
It - Italian
Pe - Persian
Pl - Polish
Po - Portuguese
Ru - Russian
Sp - Spanish
Sw - Swedish
Tu - Turkish
Uk - English
Us - American
Us_trib - American Tribal...
If someone want to don't hear any kind of it in game just delete or better rename your voices.pack in data folder.
Ps. sory for my poor english & have fun!