This game has Google login only, therefore only unsigned mod is possible
You can use Virtual Master app for root
How to root Virtual Master & install Xposed
Virtual Master - Android Clone app does not have switches to turn on root and Xposed in settings, but there is a secret way to root and install xposed easly. This is intended to avoid the violation of the terms of service of Play Store. The developer has told peoples in Telegram Group to do this...