BIOS is M5A97 R2.0
Because ASUS removed the Core Unlocker feature from the BIOS.
In a very old article it seems to be mentioned that it can be modified, but I can't find teaching.
If my own modification fails, I will come back to ask everyone.
I hope that good people can help, thank you all again.

Original discussion:
Is it possible to change a BIOS "GUI"?

This is difficult mod to do, and may not work even if added, since they've fully removed from the BIOS and it's not just a hidden option (setting is completely missing from setup module)
I think @lordkag or @CodeRush have written a guide on how to add something like that, but I'm not 100% sure, if they did maybe they can give you link to their guide once they read this

It's much easier to add if still within the BIOS modules, but still difficult to do, what you need is to add something that's not there at all and has a pretty detailed function to it so I'm not sure if this would be possible to do.

Hello
My motherboard is actually "M5A97", not "M5A97 R2.0"
(herein referred to as R1 and R2 for short)
These two motherboards have similar PCB design. I can flash the R2 BIOS into R1.
I discovered that Core Unlocker was removed, so I will come here to request how to add this feature.
R1 does not have a fast boot function, R2 does not have Core Unlocker >__<

It’s hard to decide... I think there are only two options left.
A. Drop the X3 435 and replace it with the FX-8350.
B. Use R1's BIOS, when nothing happens

Since you have R1, why did you show image of R2 with setting you wanted, and put R2 in your first sentence?

R1 BIOS already has this core unlocker option you wanted, and that is the proper BIOS for your board, so? Nothing to do there, use BIOS as it is, it has the setting you wanted
So, the setting you actually need is Fast Boot? If yes, same thing I mentioned above applies, only it's not as highly functional setting that's missing with that setting, but still it's not there to enable

This thread might help give you some ideas, but these kind of edits are mainly for options that are missing in the BIOS (but still actually present in the code itself)
Add option in AMI UEFI bios menu (how to?) (2)

And see pages 14-16 here
[Request] How to Access Locked/Hidden BIOS Menu Settings (14)
as well as this guide >> https://forums.overclockers.ru/viewtopic.php?f=25&t=599984

@davidm71 - may also be able to advise you about this, as well as @Mov AX, 0xDEAD