App is free to play, meaning the app itself would still be $0,00. In-app purchases would suddenly have to run over the google in-app purchase API if running from the play store, which would mean implementing entirely different code just for that version. I doubt Epic would want the epic clusterfuckery that comes with running 2 versions of the same software. Thus it'll be EITHER running through google play store OR running from a side-loaded APK.