I am working with this integration, which is pretty complicated. When searching your website I find this: https://docs.microsoft.com/en-us/gaming/playfab/features/authentication/platform-specific-authentication/google-sign-in-unity
However, this is from 2017 and is pretty outdated. It also state that you will update the video but when?
I guess I am not the only one that is struggling with this concept.
Cheers