Any smartphone should have the storage space built in for 11GB, especially modern phones. It's up to you to make room if you would like. The original size is close to 100GB so it's very compressed.
I need to look more into bypassing the 2GB limit .apk has. But it will never be that small without removing large chunks of the game or reducing the quality so much you can barely tell what you're looking at. It's already compressed by almost 90% so any more is hard.
I'm confused over the apk limit, most high quality games on mobile nowadays easily exceed that, I've seen some that were 10 to 20gb. What about developing an apk, and then a separate folder that has the bulk of the game content? Or maybe have the apk have a built in updater that downloads the content in itself, ive seen a couple vn's have that feature after the file size became too large over time