Obviously the voicelines of japanese come from after war japan which it had been deeply “americanfication”. You can clearly hear some phrases like "Sir yes sir./ Thank you/ 全ターゲット(target)狙え ". It could never happened during WW2. Because japan launched a huge project of “De-english”, which aims to replace all the words influenced by english or include english letters with japanese-chinese characters . For example
マイクロホン(microphone)-------送话器
キャラメル(caramel)----------軍糧精
So please delete all the voiceline with english words, it s impossible to happen at that time.
For now what i found. There re “Yes sir.”/“Thank you.” and all the phrases of “aggressive”
Just in case, surely among civilians there were social movements to remove enemy counties word, but Japanese armed forces keep use foreign words.
But… I agree currently voices are very strange. It seems too modern and using words used since after war.
Needless to say but Japanese have own military words, but this game’s voice use sound transcription of them like grenade (手榴弾 / グレネード), magazine (マガジン/弾倉) etc. Apparently, translators don’t know such words, and they selected modern words used by people who not familiar military things, not standard words used by former Japanese army. (Probably they used google translator. It generate sound transcription for such words)
It sounds native. However, even if voice actors are native, it is difficult to find mistakes. Needless to say but not many people know military terminology.
Even the Soviet voices in RO2 are gold standard for Red Army voice acting as the Enlisted ones just have not enough cursing and other authentic lines like Fritz, Smert Fashistam, etc.
They don’t even have enough voicelines going on in general. Pretty sure they actually had that like over a year ago, but they removed it. There’s also no sound when people die which is one of the reasons that RO2 and RS were cool