Embed a preloaded cache storage in the APK ?

[JAWAwebgames]

Hi,
I'm developing a PWA game that I'd love to put on the playstore, and PWA builder seems to be the perfect to do so.
On the first launch, I trigger a script to preload all the required game assets, so as the game can be completely played offline later.
I was wondering if there's a way to embed this complete cache storage in the built APK ? (considering that the app also has it's own refresh/update mechanism).
Thanks a lot.
Julien