What happens if I disable Google app? If I disable Google app (which came preinstalled on my phone and which I don't use) will that have an effect on other apps by Google like Google Maps or Gmail?

I want to disable it for privacy reasons but I don't want other apps to be affected.
No, it won't have any affect on other Google apps. I have it disabled in my phone.
Here are the things I can't use anymore:


Search widget at homescreen. I have removed it anyways. 
Google assistant. 


I've basically never missed anything with the Google app disabled. Maps, Gmail, contacts sync and everything else works as they should. I don't see them having any connection with Google app. 

However there will be issues if you disable Google Play Services app.