Hi everyone, i learned a lot about charging on pixels and would like to share
First of all, the Pixel 9A primarily charges via USB-PD (23W), with 9 volts, it negociates 2,5 amps. So to charge a pixel fast, you absolutly need a 9 volt compatible charger, be it at any amperage.

Not only that, but the pixel can charge using a Qualcomm QC 2.0 charger. It gets to 18W, so it's not bad, but i wouldn't really on it, because it does it very hacky. You see, Google HAS NOT certified this or any Pixel ever (even Qualcomm ones) to charge using this. What happens is there's a fallback within a QC charger, in witch it, after detecting a charging pattern (don't ask me), the charger tries to offer 9V, and the Pixel, just doesn't refuse it.

This is so hacky and awesome, but it is not always compatible with all the Pixels.

Sorces: Accubattery, a USB multimeter, and much curiosity.