There is no way to make a network request faster than a function call.

Apologies in advance if this it too pedantic, but this isn't necessarily true. If you're talking about an operation call that takes ~seconds to run, then the network overhead is negligible. And if you need specialized hardware for it, then it definitely could be delegate it out to a separate machine over the network. Examples could include requiring a GPU, more RAM, or even a faster CPU if your main application is running on more power-efficient CPUs.

I'm not saying that this is true in every case - they are definitely niche cases. But I definitely wouldn't say that network requests are never faster than local function calls.