Hmmm Yhwach with Schrifts :/
So, first of all this is 5-B Gilgamesh right? (5-B with full power Enuma Elish) If so, while Gil does have AP and Resistance it seems like he lack necessary durability to survive a hit :/ But ignore this first paragraph if this is Original Power Gilgamesh(5-A)
Anyway about the A fate manip, I think its important to note that Yhwach can use A on himself to somewhat avoid Gil Resistance to fate manip, for example is what he does to Ichigo when he chose to
break IchigoBankaiand
horn through the future, he also can use A to
teleporthimself as if he already there, or when
Yhwach rewrite his own Future in which he is die, in addition even if his opponent can somewhat block his attack he can change the future to where his own attack has landed and thus
bypassing his opponent ability to block his attack, bear in mind orihime barrier is not an ordinary barrier since her barrier can
rejectKōtotsu A being that is not made from
reiatsu and even
Soul society cannot do anything against it, and being
chased by Kōtotsu will also throw you into different period in time.
So Yhwach do have a way to maneuvering against Gil resistant to Fate manip by manipulate his own Fate, not to mention A don't require Yhwach to
physically react to counter his opponent attack while Gil precog require him to do so, plus Yhwach have another advantage in precog department since he dont need to analyzing all the information from the future,
everthing that he see he can also understands and there are no distinction between
understanding and having a pla. Mimihagi can also potentially make Yhwach undetected from Gil precog too and dont forget that Yhwach open portal to another dimension(bleach has do dimensional travel ever since chapter one) in case if he faced against unblocked attack and with his precog he will know which attack that he can block and which attack that he cannot do anything about it other than avoid it, so he have a ways to maneuvering against Gil Attack and resistant to fate manip.
Now let's talk about Schrifts and Yhwach other ability, while most of them is pretty useless in this situation some of them can be really handy here as example I don't see resistant to power absorb on Gil profile :/ so Sankt Altar can be an option here and for Schrifts.
Yhwach can use The Balance to counter most of Gil attack too, now I will not try to explain how B offensive capability work since Gil has resistant to it so it prob wont work but Yhwach can still use B defensive ability in form of Freund Schild who will absorb all the incoming misforture/damage to Yhwach and reflect it back at opponent so even if B misforture reflection wont work, B will still protect Yhwach by absorb all the incoming misforture on him.
X Axis as I dont see Gil to have resistant to X axis and don't forget that X axis have instant attack speed, you can only aim dodge it and it will be way harder to do so if you don't have precog(Don't forget Mimihagi here), Yhwach can snipe him in the head and be done with it. in addition X axis give him pretty good Intangibility too, shinigami who can interact with non corporeal fodder soul can't touch X axis at all, not without hax.
The Visionary. What it do? can turn fantasy into reality and on this case Yhwach can use V to erase the
image of his death thus he wont die anymore(Remember kenpachi don't kill Gremmy but he is die by literally killing himself and imagine a world where he can't imagine anymore) in adition Yhwach can create clones of himself with The Visionary to increasing his power and thse clones will be as
powerfull as Yhwach himself, so far by Gremmy feats he can create 6 clones of himself (7+ original Gremmy).
Another V is the Vanishing point(Guenael ability and he is created by Gremmy) this allow the user to
disappear from visual and mental perception at will. Upon vanishing, his opponent cannot even remember striking him, as Yachiru instantly forgot upon Guenael disappearing. Vanishing Point functions through three separate versions. By switching from Version 2 to Version 1, Guenael can remain invisible while attacking his opponents. Furthermore, he can switch between Versions 1 and 2 instantaneously" this ability has 3 Version:
Version 1 causes Guenael's "appearance" to vanish, thereby turning him invisible.
Version 2 causes his "existence" to vanish, causing him to become completely intangible. When using this version, he leaves behind an afterimage that can act as a decoy, giving opponents the impression that their attacks have landed.
Version 3 causes Guenael's existence to vanish from within the minds of others, causing them to forget that he ever existed.
The Vanishing point also has another ability that allow the user to temporally react with
faster reaction time than his opponent may have.
The Yourself. Simple it allow Yhwach to copy his opponent Appearance/Personality/Power and Memory. This can be pretty deadly ability combine with The Visionary ability to create multiple clones of yourself. :/
The Miracle. Gave him low godly regen and become stronger if your attack dont kill him..now I know low godly regen alone won't save you from Gil but bear in mind that Yhwach have resistant to soul manip(95% char in bleach have this) so its not that easy to destroy his soul, multiple ability who allow him to become Intangibility, can P Null his enemy ability via the A (Works to Conceptual power null, Causality manipulation and EE who use
100 nights in soul society), can also lower his enemy resistant and gain resistant with The Deathdealing, Can absorb all the incoming misforture/damage to his Freund Schild, Can erase the image of his death via The Visionary and even if he die he can rewrite the future where he die. :/
So overall I think Yhwach have the mean to countering both Gill resistant and Gill hax. :/