It's all in the voice actor they choose. Look at Prince of Qin, why do the Chinese sound English with broken sentences? It's all a part of what they can afford, where the game dialogue is recorded, and the budget in translation if needed.
This is a fantasy world as well, so at the end of the day, no one really knows how they sound! How would an Elf really sound? Or a smart Ogre, compared to a dumb one? Voice acting can be fun, but this is why I like only text in games, I get to create it with my own imagination.