When you select the common LaunchScreen.storyboard file, Xcode will always show it as part of App2, although it technically is also of App1, as said per the project.pbxproj.
I'm using a common file, in this case the LaunchScreen.storyboard, that I moved outside of the App1 Folder which was created when I first did the App. In the Finder it's a simple copy of Base.lproj, and then I kept Main.storyboard in the Project while deleting the other file.
As far as the .xcodeproj goes, you could probably delete the now red Storyboard, but I just edited it by using project.pbxproj in a Text Editor by using ../Base.lproj/LaunchScreen.storyboard instead of Base.lproj/LaunchScreen.storyboard.
I then create a second App, similar, where I simply did the same editing of project.pbxproj and then removed the useless Storyboard in the Finder, since I refer to the files at the root of this git Repo, in Base.lproj.
Open CommonLaunchScreen.xcworkspace and choose both LaunchScreen.storyboard files, you'll see how Xcode acts.
This is not happening if I move the Base.lproj in the Workspace.
This is not happening with ViewController.swift, which I also reference globally. That is, as long as this file isn't in Base.lproj, so I suspect the interpretation of Xcode has something to do with a folder.
