F3 (2018-07) version says " 1. Bootable with Intel 9000 CPU"
as you said, for 9100 is stated F12… so a dilema here from Gigabyte??? Ask them…
906EB Coffee Lake-S (B0)
cpu906EB _plat02_ver00000072 _2017-09-20_PRD_A08C2841.bin
[OFFER] Intel CPU Microcode Archives - Special Topics / CPU Microcodes - Win-Raid Forum (level1techs.com)
Replace it in F3 or F12… will it work in F3, same dilema…
Now once and for all… all mods have their RISKS, so NEVER ask if it breaks or not cause no one can assure you, a fail safe sucessufull operation in mods.
Users want this and that and so on, but have afraid and dont want to break their system… that’s not viable in mods scenarios… take the risks or NOT, simple as that.