Screw WhatsApp. That's what you should be getting away from anyway.
And install CopperheadOS on your phone. It doesn't use any Google services.
It even has a list of its defaul connections made by the OS:
https://copperhead.co/android/docs/usage_guide#default-conne...
Unfortunately, support for Nexus devices will soon be gone and the Pixel 2 devices with pre-installed CopperheadOS are quite pricey for private use.
You can always just compile it yourself for your own Pixel 2 device. Or use LineageOS which runs on a far wider range of devices and doesn't charge $500 for binaries.
I know WhatsApp isn't perfect, but I wish most people where I lived used it. Well I wish they used anything really. I'm one of my few friends on Android, and it is really annoying being excluded from group chats because of it.
Unfortunately, support for Nexus devices will soon be gone and the Pixel 2 devices with pre-installed CopperheadOS are quite pricey for private use.