Crash when trying to add account

When trying to add an account in the system settings, GmsCore crashes.
Logcat: https://pastebin.com/RaU7tcS5
Device: BQ Aquaris X Pro (bardock-pro)
Firmware: Rooted Stock Android 7.1.1 with TWRP
Steps to reproduce:

• Fresh install of stock firmware from https://www.bq.com/de/support/aquaris-x-pro/support-sheet

• Install TWRP via fastboot, boot into TWRP, adb sideload Magisk, normal boot

• Install Magisk module Debloater: https://forum.xda-developers.com/apps/magisk/module-terminal-debloater-debloat-t3584163

• Use debloater to remove: Calendar, Chrome, Drive, Duo, Gmail, Google Contacts Sync, Google Text-to-speech Engine, Hangouts, Keep, Google Keyboard, Maps, Messages, Google Play Music, Photos, Google Play Movies, YouTube, Google Play services, Google Backup Transport, Google One Time Init, Google Partner Setup, Google Services Framework, Google Play Store, Google

• Install Xposed framework

• Install Xposed module FakeGApps

• Install F-Droid

• Install GmsCore and GsfProxy from the microG-F-droid-repo

• Configure microG (All boxes checked)

• Go to System Settings > Accounts > Add Account

• GmsCore crashes

Start by reviewing the linked Logcat and reproducing the crash from System Settings > Accounts > Add Account in the listed microG and GmsCore setup. Trace the crash from the account-add flow; done means identifying and fixing the cause so adding an account no longer crashes in this environment.