Google Analytics never uses browser fingerprints. The default tracking scripts only use first-party cookies. If you call the GA API directly, you don't even need cookies or local storage. This will make some of the reports meaningless, of course. The user's IP address is obviously sent, but it can be truncated by setting an option.
> The user's IP address is obviously sent, but it can be truncated by setting an option.
The IP address is inherently sent due to how the internet operates (unless you proxy GA calls through your server, which I'm not sure is even possible).
The option to "truncate" the IP address just tells Google you don't want to store it for your analytics. It has no effect on whether Google still keeps it on their side for their own benefit.
I'm not sure if this is doable by proxying through the server, so only custom events (with an unrelated IP - the server's one) are sent.