[BUG] NSUserDefaults are not written to App's respective directories

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Describe the bug

I found that although apps write almost all their files to their respective folders, their NSUserDefaults are still written to LiveContainer's Library/Preferences, which creates a mess in that folder and is hard for users to move apps to other devices.
I wander if it's possible to redirect NSUserDefaults writes to some folder in Document?

Instructions to reproduce

Install any app that uses NSUserDefaults and check LiveContainer's Library/Preferences

What version of LiveContainer are you using?

2.1.2

Other info

I dumped symbols of NSUserDefaults class and didn't find any way to set a path. I wonder if it's hard coded into that class, or it uses a different environment variable other than HOME?
I also tried to create a symlink but iOS didn't allow any write to Library/Preferences folder it self.

There is a method caller -[NSUserDefaults _initWithSuiteName:container:] but it seems that not all NSUserDefaults are instantiated by this method.

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I found a method -[NSUserDefaults _container] that I can hook to redirect most NSUserDefaults write to other location, but some still write directly to Library/Preferences