I'll put it out there for you.
I found this way, it's probably crude. Checked it in the store, it works.
You need to find the file "GameName-Info.plist" and add variables with the desired languages as on the screenshot.
I want to remind you that you have to make localization of your game as you like, with the help of plugin or array or dictionary. This method will simply add a list of languages to the Apple Store page and if a player downloads and the game does not have his language inside, it will be a scam.