With reference to Answer by "QuinceyMorris" - https://developer.apple.com/forums/profile/QuinceyMorris :
Actually the text on label can get localized, if we uncheck "Static Text" in Accessibility settings
Steps :-
1) Localize "LaunchScreen.storyboard" file. That file should BE localized as follows:
Create a new iOS project from the Single View App template.
In the project editor, add a localization.
As this in the first localization (other than the the base), Xcode will ask you which files you want to localize. It does this by showing you a list of localize files, where all files start out as checked. Keep them checked.
2) Open "LaunchScreen.storyboard"
Add Label and select it.
3) in "Show the File Inspector" tab (first tab)
'Check' all your localization including Base.
3) in "Show the Identity Inspector" tab
Note the "Object Id" in Document section
in "Accessibility" section
'Uncheck' Static Text option.
4) All your LaunchScreen.strings files should have following text to localize.
eg. LaunchScreen.strings (English)
/* "<<Label's Object Id.text>>" = "<<Localized text>>"; */
"17x-cE-Ge9.text" = "Sanjay's Swift Application";
eg. LaunchScreen.strings (Gujarati (India))
/* "<<Label's Object Id.text>>" = "<<Localized text>>"; */
"17x-cE-Ge9.text" = "સંજયની સ્વીફ્ટ એપ્લિકેશન";