I was stuck on my S8+ and followed the instructions from this guide:not sure this is true... https://github.com/microg/GmsCore/wiki says under System Requirements:
Makes me think I need it on a more or less stock A12 rom for my Samsung S10+
Anyhow, my sequence in the end was (I think):
1) debloat / remove google components from stock rom
2) install whew-inc's fakegapps fork in LSposed
3) install Fakestore from microG
4) install GmsCore + Framework from microG
5) make sure sig spoofing is active in LSposed>fakeGapps for the microG components
6) a reboot may be helpful ("into recovery" from inside magisk to ensure root is back after reboot)
7) configure microG inside microG app
Seems to work...so far.
microG This guide will receive updates and changes as they happen in microG! microG is Freedom, Security & Privacy from Google, by replacing the Google Services & Framwork, also improving phone and battery performance! This guide shows you...
I had to make the last step on my android 10 version, Install the F-Droid Privileged Extension - Read about it here; https://f-droid.org/en/packages/org.fdroid.fdroid.privileged/
This guide saved me a ton of time and have set my device with all boxes ticked. Running Hades ROM Q3 on a dream2lte device (exynos)