Your Motherboard doesn't have USB BIOS FLASHBACK feature which allows you to update the BIOS without a CPU installed.
Thus you must enter BIOS to use the BIOS Updating programs and if your CPU is not compatible due to the wrong BIOS version installed you won't be able to enter BIOS to update the BIOS version thus you will need a CPU that is compatible with the BIOS Version installed on your Motherboard.
But the 2 BIOS versions that support the Athlon 200GE is BIOS versions 4011 (05/02/2018) or 4406 (03/11/2019).
If you purchased the Motherboard recently it should have the latest BIOS Version installed from the date of the Motherboard's being manufactured.
Thus the Athlon 200GE should work out of the box if the Retailer sends you a Motherboard manufactured after 03/11/2019.
When you receive the Asus motherboard, there is a slim white sticker next to the CPU socket or DIMM Slots. At the end of the second line there will be a 4 digit number. That is the BIOS version installed on your motherboard in case it isn't listed on the Retail box.