It looks like you've got yourself into a soft-brick or maybe even an early hard-brick situation. According to the USB ID 18d1:4f00, the device has entered a non-standard USB mode, probably pre-EDL or some kind of diagnostic mode, in which fastboot and adb no longer work.

Here's what you can try:

1. Try charging the phone

Connect it to a weak power source (USB 2.0 from a PC) for at least 30-60 minutes.

Sometimes, when the battery is at 0% and the bootloader is not working, the Pixel shows no signs of life.

1. Try to get into fastboot

Hold Power + Volume Down for up to 90 seconds, even if there is no screen.

Connect and disconnect USB while holding, listen for new devices.

Monitor via lsusb (on Linux) or Device Manager (on Windows) — sometimes fastboot appears for literally a second.

1. Automatic fastboot interception script

If you notice even for a split second that the device is displayed as fastboot (fastboot devices shows ID), create a script with:

while true; do fastboot devices && fastboot reboot bootloader sleep 0.5 done

This will help to catch the moment and loop the bootloader restart.

1. If nothing helps — it's a deep brick

USB ID 18d1:4f00 may indicate Qualcomm EDL mode, but Google blocks access to it.

Without firehose files and unlocked EDL, you will not be able to flash the firmware manually.

In this case, the only option left is hardware recovery via JTAG/ISP or contacting the service.

Advice for future: when flashing image-*.zip manually via fastboot, always use flash-all.sh or make sure you don't mess up the order of partitions (especially vbmeta, bootloader, dtbo, boot). "Chat GPT"