Assumptions:
Void Dark/Light do nothing.
Free skill inheritence except where restricted in-game (for example, only Alice can use Die for Me!)
Myria (BoFs)- Myria. She needs Paralysis from BoFIII form, but that's pretty decisive.
Ghaleon (Lunars)- Ghaleon. Most generous possible interp in Souji's favor probably takes this? he needs Ghaleon to not be able to spam Fate Storm (That is, Fate Storm+Fate Storm combos), to double him very quickly, and a few other things, all of which adds up to quite a stretch.
Zophar (Lunar EBC)- Zophar. Status ball.
Lady (SH3)- Souji. Looking at it... Souji can probably pull off the first hit. Thinking he scrapes the 2HKO even without Auto-Taru... may need to though. If Lady goes before Umbral, Entrance+Calamity Gaze is a OHKO, so that x2 plus Final Attack would be fatal, so in that scenario he can't let her get a second turn. Mind, if that didn't happen (ie Umbral goes first), he's fine, gets in another chipping move on his first HP bar and seals the deal.
Fou-lu (BoFIV)- Souji. Astral is a straightforward win for him, milk his speed (and/or use his magic dodging accessory, if that floats your boat better) and wear Fou down. Tyrant is weird, he loses his first HP bar to Dark wave no matter what he does, but Fire is consistent enough damage on Fou that he should get Fou under OHKO level before his second turn and the above applies.
Yuna (FFX)- Souji. Sources tell me that Souji's listed ID percentages are very low. He needs the ID here, Yuna evade kicks his ass.
Piastol (SoA)- Souji. She goes first, so he only gets one shot of Hassou Tobi in (first life bar is IDed, second gets in an attack, ID again to knock to 1hp). Buuuut... Auto-Taru+that+fully amped spell... shouuuuld be enough.
Sephiroth (FFVII)- hmmmm. Souji. Physical moves in P4 don't scan as melee to me, so no turn 1 fly hype. After that, can either OHKO or 2HKO through Wall, neither ends in a Sephy victory.
Jenna Angel (DDS)- Souji. straightforward Enduring Soul+Endure.
Jade (BoF1)- Souji
Kefka (FFVI)- Souji. Finally into the OHKO whores he likes!!
Yuri Hyuga (SHs)- Souji. Should still OHKO through For Everyone.
Ryu (BoFIII)- Souji
Heat (DDS)- Well, I make Heat take a turn to summon the tentacles. Souji. Without that... dicey. Souji can stall for a while, but... I don't think he OHKOs, Heat murders him after a Hassou, and I don't think he can stall long enough to use non-physical offense on his "smite Heat" turns.
Xorn (G3)- Well. If Xorn has anything better than a 3-2 turn split in his favor, he wins. This requires 1.24x average speed on Souji's part. You'd have to take his speed literally to achieve this so uh... yeah Xorn. Edit: duurr, pure physical/wind. Souji
Melfice (G2)- Souji. Melfice has a non-P4 element! And is only like half Xorn's speed! And laughs off Hassou! Souji still gets four whacks at him, it's enough.
Emelious (G3)- Souji. Easier, Emelious' non-Physical damage isn't as good as Melfice's and he has to spend a turn for that evade. This makes up his minor statistical advantages.
Profound Darkness (PSIV)- Souji. The word OHKO is used a lot in the match summary, but it ends in his favor. More blatantly so if you let him null Light/Dark damage.
Cloud of Darkness (FFIII)- CoD. Toad.
Luis Virgil (XSs)- Souji. He can stall the first form indefinitely (it's dependant on Ice/Lightning/Fire), and thus should be able to set himself up to OHKO the second form once it comes out. He needs to; Stop is a loss, but he should be able to manipulate things in his favor.
TimeLord (SaGa Frontier)- TL
Loki (VP1)- Souji.
Empyrea (DQVIII)- Souji
Lavos (CT)- Souji. Hmmm. Looking at it, taken as presented in game he ties it up forever, taking it in a simpler form just involves surviving a OHKO and going from there.
Indalecio (SO2)- Souji
Isolde Schelling (MK)- ... not totally sure, but leaning Souji? She needs to get turns at under 50% HP and spam Bunker at him until death, dunno if he can manipulate his way around that for sure.
Nate Nanjo (Pers)- P2. Souji
Ellen Kirashima (Pers)- P2. Souji.
Kuja (FFIX)- Souji
Violetta (G3)- Souji. She has one 600 damage spell that hurts him. That'll work.
Citan Uzuki (XG)- Souji
Kyogre (Pkmn)- Souji
Terra Branford (FFVI)- See Yuna. Souji.
Van (TotA)- Souji
Avalon (LoL2)- No vote.
Ryu (BoFIV)- Souji
False Althena (Lunar EBC)- Souji
Luca Blight (S2)- Souji
Chaos (FF1)- Souji I'm reasonably sure. Power Charge if needs be.
Chris Lightfellow (S3)- Souji.
Rika (PSIV)- Souji
Tir McDohl (Suikos)- Souji
Deamoned (BoFV)- Souji
Ted (SuikoIV)- Souji
Dhaos (ToP)- GBA form. Souji
Rubicant (FFIV)- Souji
Belial (WA4)- Belial. Stupid 4D pocket.
Elc (AtLC)- No vote.
Royce (Lunar SSSC)- Royce. Looks like she has some NE damage to get through with while encasing him.
Orlandu (FFT)- Souji
Guv (DQVIII)- Souji
Ramirez (SoA)- Souji. It's chibi-Piastol >.>
Patriarch (XS2)- Souji. Thought about hyping Curse, but nah, just plays around and smites via Power charge.
'Zenon' (Dis2)- Souji. Attacks for free before 50% HP for starters.
Zeromus (FFIV)- Souji
Seymour (FFX)- Souji
Mewtwo (Pkmn)- Souji
Yunalesca (FFX)- Souji. Any regen lets him get to form 3 on his first HP bar, and I tend to think he whittles form 3 down fast enough.
Oddeye (ShF2)- No vote.
Malik Benedict (WA3)- Silence and Confuse are on the list of things Souji can catch! Souji
Rhapthorne (DQVIII)- Souji
Rolf Landale (PSII)- No vote.
Arc (AtLC)- No vote.
Lamington (Dis1)- Souji
Beatrix (FFIX)- Souji
Ultimecia (FFVIII)- I'm just going to assume. Souji
Shania (SH3)- See Yuri more or less. Souji
Cecilia (WA1)- Souji
Dark Force (PSs)- Souji.
Ash Lambert (VH)- NO vote.
Tibarn (FE9)- Souji. ID.
Albedo (XSs)- Souji
Gilbert (SH3)- Souji
Killer (SH3)- Souji
Naesala (FE9)- Souji
Rashidi (OB)- No vote.
Endora (OB)- No vote.
Luther Lansfeld (SO3)- Souji. Power Charge, OHKO.
Deis (BoFs)- Souji
X (MMXCM)- Souji
Claude Kenni (SO2)- Souji
Lambda Zellweger (WA4)- Souji. He only has to hit once and all.
Miguel (CC)- Souji
Necrosaro (DWIV)- Souji
Riou (S2)- Souji
Teepo (BoFIII)- Souji.
Johnny Garland (SH3)- Souji
Gades (Lufias)- Souji
Millenia (G2)- Souji
Choko (AtLs)- AtL4 choko. Souji
Celes Chere (FFVI)- See Yuna. Souji
Rosa Harvey (FFIV)- Souji
Brahms (VPs)- Souji
Lugia (Pkmn)- Souji
Jecht (FFX)- Jecht!!. he really is the best.
Marino (MMXCM)- Marino. Think she's... slllliiiiightly faster. Thus, multiple ID applications and victory!
Kurando Inugami (SH2)- Souji.
Jessica Albert (DQVIII)- Souji
Zog (BoF1)- Souji
Dhoulmagus (DQVIII)- Souji
Raquel Applegate (WA4)- Souji. Applies Silence. After that she can't damage him, she shouldn't be able to kill him in the interim.
Asgard (WA3)- Souji
Altima (FFT)- Souji
Eirika (FE8)- Souji. ID if you disrespect his damage against evade particularly.
Valvalis (FFIV)- Valvalis. Don't... really see a way for him to kill her fast enough to prevent petrification.
Genevieve (VP1)- Souji
Lulu (FFX)- Souji
Lenneth Valkyrie (VP1)- Souji
Zio (PSIV)- Souji
Id (XG)- Souji
X-Death (FFV)- ... X-Death. Man, now I wish there was Auto-Power Charge. Edit: Second thought, what'm I thinking, he should OHKO. Souji
Nel Zelpher (SO3)- Souji
T260G (SaGa Frontier)- Souji. He might only 2HKO? But windup turn makes that moot.
Xenobia (Lunar SSSC)- Xenobia
Sir Leopold (DQVIII)- Souji
Cyril (SO2)- Souji
Gilgamesh (FFV)- Gilgamesh. Frog
KOS-MOS (XSs)- Souji
Emily (S3)- Souji
Sierra Mikain (S2)- Souji
Ryu (BoF2)- Souji
Lucia (Suikos)- Souji
Tidus (FFX)- Souji.
Berle (SO2)- Souji
Purim (SoM)- No vote.
Kratos Aurion (ToS)- Souji
Magus (CT)- Souji
Diekbeck (AtLs)- AtL4. Souji
Chaz Ashley (PSIV)- Souji.
129 Godlikes total.
9 no votes.
1 undecided vote.
12 losses out of 119 possible. Or, 106/119 wins. Worth noting here that, if we supposed that Void Dark/Light was equivelent to ID immunity, he'd probably beat Ghaleon and Marino too.