To use an AMD Ryzen 7 9800X3D processor with this motherboard, it is strongly recommended to update the BIOS before installing the CPU and booting the PC, as compatibility with Ryzen 9000 series processors generally requires a recent version of the BIOS.
The most recent version available on the official ASUS website (3279) improves compatibility and stability, but there is no explicit official confirmation that the 9800X3D is immediately supported without prior update.
User feedback indicates that the 9800X3D works with recent BIOSes (e.g. 3265), but memory compatibility or boot problems may occur if the BIOS is not up to date.
If in doubt, it is advisable to update the BIOS using the BIOS FlashBack function (without a CPU installed) to ensure optimum compatibility.
If you need official confirmation, check the CPU compatibility list on the ASUS website or contact ASUS technical support for your country.

Unfortunately, we do not know which BIOS version is installed on the mainboard. However, the board supports a method for updating the firmware without an installed CPU:

"BIOS FlashBack™
BIOS FlashBack™ is a safe and easy way to update the BIOS. Simply place the (UEFI) BIOS file on a FAT32 formatted USB stick, insert it into the USB BIOS FlashBack port and press the button. Updates can even be performed without memory or a CPU installed."

Do you know which BIOS version will be installed when I receive the motherboard?