Sure, it was a bit annoying but here is my rough process:
1) Find the dialogue assets by just searching and filtering through FModel. I found that they were mostly in datatables like many Unreal games (prefixed with DT_).
2) Extract all the "DT_*" assets with retoc, using a command like:
	
	
	
		Code:
	
	
			./retoc.exe to-legacy --no-shaders --no-compres-shaders -f "DT_" "$GAME_PATH" output_dir
	 
 3) Open the files you want in UAssetGUI. For the dialogue lines, I found them in this file:
	
	
	
		Code:
	
	
			output_dir\GalHome\Content\0_GalHomeNew\Managers\StoryAdvManagerSubsystem\DT_StoryGalBeforeLife.uasset
	 
 4) Export the .uasset file to .json (in UAssetGUI)
5) Translate all the lines in the .json from JP -> EN. They're usually under "CultureInvariantString" keys with various levels of nesting. I just wrote a python script to do this.
6) Import your modified .json into UAssetGUI, then export it out to .uasset (there has to be a better way to do this tho...)
7) Create a final directory structure with all of your modified files that you want to include in the final pak mod. It's important that the structure is identical, so the previous file would go here (assuming your mod is in a directory called `mod_files`):
	
	
	
		Code:
	
	
			mod_files\GalHome\Content\0_GalHomeNew\Managers\StoryAdvManagerSubsystem\DT_StoryGalBeforeLife.uasset
	 
 8) Package everything up with retoc:
	
	
	
		Code:
	
	
			./retoc.exe to-zen mod_files "TranslationMod_P.utoc" --version UE5_2
	 
 
Kind of a hassle but I usually follow a similar process for most of my UE mods. Hopefully that helps tho!