Well, here we go. I might update it with more information down the road:
His cr. forward and sweep are slow in comparison to shoto standards.
His other normals such as st. strong and cr. strong are effective.
Has Akuma’s normals (cr. fierce, st. far fierce, etc) but seem to be slightly slower.
Walk speed is like Akuma, dash and backdash are quick but active.
Hop kick is slow, seems to be safe on block. It can avoid throws and punish OS techs.
Axe kick seems to be unsafe on block on all versions, need to test short version again but I’m sure I got DP’d on block.
Teleport is bad unless used in very specific situations, slower and less range than Akuma’s, very punishable.
Dive Kick is better than Akuma’s regular Dive Kick in terms of hitbox and advantage, but it is slower.
Both Ultras do okay damage, but nothing crazy.
Fireballs are Ryu speed, EX does not knock down. Traditional shoto footsies work with fireball.
Red fireball is identical to Akuma’s.
All of his DP’s are great, jab DP has more invincibility to anti air with similar to vanilla Ryu.
Conclusion: I cannot find a good reason to play him over Akuma. Akuma does everything better and more efficiently, and has a vortex.
Now for my favorite part:
Has normal walk speed.
Great dash, great backdash, great normals.
Oni has multiple variations of his normals. He can do things like st. strong, back strong, st. forward, back-forward, etc to use different normals.
He can do Akuma and Ryu combos minus tatsu-DP.
Oni can chain his normals into specials without having to link them. For example, cr. short/jab/short combos immediately into roundhouse tatsu without delay.
He has a slower version of Ken’s stepkick by doing Towards + Forward. You can kara grab with this although the range is similar to Akuma’s. You can also kara standing forward.
ANTI AIR OPTIONS:
ST. FORWARD: AMAZING TOOL. Stuffs dive kick characters, fast, hits twice in proximity. Beats out Jaguar Kicks too from Adon. Think of Bison roundhouse!
ST. FIERCE: Anti-air proximity.
TOWARD + FIERCE: Lunging punch, one of the BEST NORMALS IN THE GAME. Reaches beyond cr. forward range, can whiff punish almost anything, slightly unsafe if used up close, eats projectiles from distance, can anti-air from range, massive hitbox, lots of active frames. Can stop jumps when used pre-emptively from range. 5 of these seem to stun average health characters.
TOWARD + ROUNDHOUSE: Chun-Li’s standing roundhouse. Have to use pre-emptively to stuff jumps. When connected as anti-air, it knocks back opponent full screen. Causes spinning animation. Can be combo’d after EX Dashing Slash.
DRAGON PUNCH: Seems to be 3 frame. use it EXACTLY like Akuma’s to net perfect anti-airs. ALL OF HIS DRAGON PUNCHES HAVE FAST RECOVERY ON GROUND. (Think of Ken’s EX DP recovery). You can combo all hits from cr.strong range (maybe further) when used as reversal. I completely stuffed Vega’s cr. strong and netted all damage + knockdown. The extra hits do not whiff like Akuma.
CROUCH FIERCE: Exactly like Akuma’s.
ULTRA 2: Nets full damage + animation when used as anti-air on reaction. Great ultra.
DEMON STOMP: Motion is Demon Flip. Short version seems to be safe on block. Can be used in strings to punish OS techs and mashing. Does good damage. EX version is two hits + overhead. None of them seem to be able to cross-up. Hitbox range on EX is like Viper EX Seismo. Others have shorter range.
AIR DASHES: All have noticeable recovery. You can cancel Forward dash and air hop into tatsu to land quicker or float more depending on timing. When used correctly, you can use the tatsu to hit crossup or just hit in general. YOU CAN SUPER CANCEL THE DASHES INTO AIR DEMON. This is how you avoid hitting opponent’s with an air jab when buffering.
REGULAR FIREBALL: Goes about 60% screen distance. Charge fully to gain 2 hits + full screen projectile. EX version just goes full screen and does 2 hits.
DRAGON PUNCH: Can’t seem to FADC it on block. You can FADC the second hit on hit, but you cannot FADC the first hit under any circumstance. All of them are great anti-airs.
BLUE ELECTRIC FIREBALL: Same as Akuma’s Red Fireball.
DASHING SLASHES: Short and forward hit in the front, roundhouse and EX hit crossup. Short seems to be safe on block. Can be grabbed like Balrog dash punches or mashed out of. If you land EX, you can follow up with U1/DP/Tatsu/Forward + Roundhouse.
Target Combo: Back + Strong, Fierce: Does not connect on crouch.
Main punish combo: Cr. Strong xx Target Combo xx Fireball/DP/Tatsu/EX tatsu. Great stun and great damage. If you end in Tatsu, you travel very far with them. Think of Ken’s EX Tatsu, except with a knockdown.
Can chain his normals into specials. So far I’ve tested this with cr. short/jab/short xx tatsu without delay and it chained fine. Can chain into standing jab like Akuma and you get Tatsu.
Linking your cr. short into jabs lets you link Tatsu/EX Tatsu/any special like Akuma.
SUPER DEMON: Same as Akuma’s. Can cancel overhead and run the same buffer routines. DASH > DEMON IS A VIABLE TACTIC BECAUSE OF ONI’S AMAZING DASH! You can buffer the jabs and finish the Demon when in proximity.
ULTRA 1 (FIREBALL): Haven’t found a solid way to link it yet outside of doing EX Dashing Slash. Air version seems to be useless. It’s slow and it pushes Oni back full screen with a lot of recovery. Have only used it as an air-to-air. If done with KKK, it goes straight up. You cannot use this to punish Ibuki’s Kunai vortex on wakeup, so take that information and come to your own conclusions. It’s too slow for that.
ULTRA 2 (KKZ): You can combo into this by doing cr. forward > EX Fireball > FADC, or you can use it as a pure anti-air. Both ways net you full animation. Amazing anti-air ultra. If you auto-correct it on wakeup against bad jumps, you can probably net it.