You can use this direct link below to grab the full working version of Google Apps installer useable on Xiaomi Mi 6X. This APK file allows you to automatically download and install all basic GApps to have a fully working Google Accounts and Play Store running on the Mi 6X. This Android app is basically an installer and not the GApps itself. What it does is searching for the compatible GApps version, download it, and install it on your device.
As usual, the APK file is hosted on our servers spread in some regions in US and EU. This file serves as mirror download link. We never change, alter, nor make any modification on it. However, we always encourage you to always scan any files you downloaded from third-parties (other than Play Store). This is a good practice for every device owner.
Also, read Google Play and Apps for MIUI 9 Based on Android 8.0/8.1 Oreo.
Download
Google-Installer-Mi6X.apk