What happens if you connect two power banks via USB-C?

Question

USB

How USB 3.1 works on a type c - type c cable:
1. Power bank - power bank connection. Who will charge whom?
2. Connection power bank - notebook. Who will charge whom?
3. Notebook-notebook connection. What happens when you try to connect?

Answer 1

power bank

Whoever decides to be charged first will be charged.

power bank-notebook

Also, but only if the power bank can do PD

notebook-notebook

In theory, no one will charge anyone then, because both will request PD, which no one can give. (I think so)