So the voice not working is because the translation, translated the command ボイスの演奏 into Voice Performance, which is the 1:1 machine translation you get from any number of online translators. The problem is that the Japanese command is one word while Voice Performance has a space. The plugin already has English commands PLAY_VOICE and STOP_VOICE.
The common event 0178 is just a shortcut to stop the voice being played, but it's also malformed. "Stop SV_Voice 2" I'm almost positive the command should be "SV_STOP_VOICE" or "SV_STOP_VOICE 2". Which should be an easy fix.
"SV_Voice Performance EV00_008 90 100 0 2"
Is what the voice command looks like currently in the translation. SV_ is the command for the Simple Voice Plugin, followed by the command "Voice Performance" and the arguments "EV00_008 90 100 0 2"
Changing the plugin to add 'Voice Performance' won't work because it has the space. It might be possible to change the plugin to add the command Voice then take the argument "Performance" do nothing at all with it then process the rest of the arguments "EV00_008 90 100 0 2" as normal. This would then fix the problem with only needing to make one edit to the common events, then edit the plugin to add in the hacked voice command and null parameter.
If any of the other RPG wizards want to chime in please do.
The other option is to run the text translator whatever and replace "Voice Performance" with either "PLAY_VOICE" or "ボイスの演奏" and then look at the common event to see if it works or not.
EDIT: Fixed the voice! Extract the attached file into /www/ and it will replace the CommonEvents.json and SimpleVoice.js with my edited version.
I changed the common event to be properly formatted to stop the voice when you skip the line. You don't need this but it works as intended now.
The SimpleVoice I added an extra command, then made the plugin ignore the first argument so it correctly plays the right file.
If someone changes the Dialog command that looks like this in the code "SV_Voice Performance EV00_008 90 100 0 2" you will break the edit I made to the SimpleVoice.js file.
These two edits should be compatible with any word wrap script.
Let me know if it stops working for other sex EVs because I only tested it on the intro.
EDIT 2: Janky word wrap fix.
The text in the code has line breaks but the YEP_Message Core that should do word wrapping ignores the game editor line breaks and wants it's own command. (this is as expected)
I don't know why the word wrap from the module isn't working, (this is not as expected) but the translation mostly fits line per line. So I turned off the YEP_Message Core and left the text as default. This may break something else in the game I don't know. Anyway attached is the file; we are replacing the plugins.js file just exact in the /www/ and it should work. Maybe back up your files? Let me know if this breaks anything else.