Google Pixel 4 (Fully Unlocked) (S&D) (Open Box)

Google Pixel 4 (Fully Unlocked) (S&D) (Open Box)

Is the bootloader locked? Or can it be unlocked to flash a non-google firmware?

The description states the bootloader is locked.

Also, they are ex-Verizon.

You need to get a non-carrier supplied (original or otherwise) phone for the bootloader to be considered possibly unlocked.