BFU inside the table cells means:
"BFU extraction can only pull the small amount of "Device Encrypted" (DE) data that is accessible. This is mostly system logs, some app settings, and other non-personal data. It does not get messages, photos, or detailed app data." It basically gets them the list of apps, when the phone has been powered on and off and perhaps some cell geo location history.
FFS means Full Filesystem Search.
What this implies in practice:
All locked stock Android Pixels (including 10 I am almost sure) are vulnerable to FFS after the first unlock, even in the locked state. If you want to protect your data (crossing a border, or when you are about to be interrogated by Russian FSB), turn off your stock Android Pixel.