Gonna go ahead and do a detailed overview using screenshots from that article and information from it and other sources.
Kum Haehyun is girl riding around in a humanoid puppet that looks like an old tough man. She's a link-based character with easy-to-input specials with follow-ups focused on either holding and releasing the attack button or moving the stick in a certain direction. Her normals tend to have a short range but deal a lot of damage. Size is similar to Potemkin, movement options aren't very good, but she can dash, airdash, and can move while while crouching.
This is her crouch. She's actually moving in this image, though it's hard to tell.
This is her projectile, Chōdengan (Tune Relay Sphere). 236+S or HS. You can actually use the stick to move it left and right after launching it. HS version is red.
This is Shi'inken (Saingeom, aka Four Tigers Sword). Standard input (623+K) is an anti-air kick (left). If you hold K she starts to spin and travel forward along the ground, hitting low multiple times, before leaping into the air with a spinning kick that hits multiple times. If you hold back on the stick after she starts spinning, you'll do a powered up version of the anti-air kick that you can gatling after.
This is Hayabusa Otoshi (Falcon Drop). It's an axe kick. 214+K. Normally it's small and blue, but you can hold K to do a powered up version (pictured) that hits harder that you can gatling after. Can also be used in the air.
This is her first Overdrive, Arahan Sanzenshō (Arhat's Three Thousand Palms). 236236+H. Has a short cinematic startup where all these extra energy palms start rotating around her mech's hands, then she does a big forward hand clasp. You can hold the button, which creates a big sphere centered on Haehyun that pulls the oppontent toward her if they're inside of it.
This is her second Overdrive, Shinkung: Chōdengan (Divine Bow: Tune Relay Sphere). 236236+S. A bigger more powerful version of Chōdengan, which you can control with the stick. Unlike the normal version of Chōdengan, you can also move this one up and down.
In her intro, she plays some notes on a zither which then transforms around her, becoming her humanoid puppet armor. After the the cockpit closes, the puppet crosses its arms.
In her win pose, the camera zooms into her cockpit and she leans back in her seat, relieved, but accidentally pushes a self-destruct button with her elbow. Warning messages start flashing on all of her monitors with a countdown while she freaks out. When the timer hits 0 the screen flashes to white.
In the cinematic for her IK, Zengen Teppai (Total Chord Elimination), the camera zooms into the cockpit and she conjures a magical zither with strings made of ki and starts to play a tune on them. The strings extend outside the puppet and wrap around the opponent, forcing them to their knees. She marches forward while delivering a lengthy speech, kneels in front of the opponent, then flicks them in the head with her finger, sending them bouncing across the ground and over the horizon.
Raven is one of That Man's three lieutennants and an immortal whose body can regenerate from any injury. He has a unique Excitement Gauge that fills when he uses his ability Koko ni Saretai ("I Want It Here!"), increasing his damage and changing the property of his attacks. His normals are on the slow side, but generally have a lot of range and a very briefly lingering slash trail that maintains the attack's hitbox even after it looks like the attack is done, so they're good for zoning. I've seen them compared to Dhalism, but it's more like he dislocates the joints in his arms and lashes them around like whips. His dash looks like a teleport, but he won't pass through the enemy.
This is his airdash. It works like a glide, angling downwards, and the steepness of the angle is determined by how high up he is when you input it. As you can see in the image, it deals damage on contact and can be used to start an air combo.
This is Koko ni Saretai. 214 + K (can be held). He'll stay in this stance until you let go of K. He'll absorb all incoming damage and fill up his Excitement Gauge. When the gauge is full his animation changes to the one pictured. Damage won't knock him out of the stance and attacks will just push him around, but he can be grabbed. Any damage he takes in this stance will slowly regen when you cancel it.
This is Grebechlich Licht (Fragile Light), 236+P or K during a jump, a downward-angled projectile. P or K determines the angle of the attack. He also has a horizontal ground projectile, Schmerz Berg (Painful Mountain), which is 236 + P. The needles used in both of these attacks will afflict the enemy with a short (1~ sec duration) slowdown.
This is Scharf Kugel (Sharp Circle), 236+HS (air ok), a spinning saw-like projectile that travels forward a bit, slows down, then spins in place briefly, like Jedah's Dio Sega from Darkstalkers. The air version travels at a downward angle with a slight forward arc.
This is Grausam Impuls (Gruesome Impulse), 236+S (air ok), a long range claw slash that knocks back and seems to be meant as a combo finisher.
This is his command grab, Wachen Zweig (Guarding Branch), 63214 + S or HS. S is pictured, HS is an anti-air. He lashes out and snags the enemy, then slams them down into the ground. If his Excitement Gauge is full, it'll bounce them up into the air for combo potential.
This is his first Overdrive, Getreuer (Loyalty). 214214+HS. Has a short range and a bit of a windup. If the first hit catches the enemy, he'll unleash an increasingly rapid flurry of slashes and then deliver a big kick with knockback. The number of hits seems to be based entirely on how full his Excitement Gauge is. It looks like it does 51 hits total with a full gauge, and 1 (just the kick) with it empty.
This is his second overdrive, Verzweifelt (Despair). 632146+S (air ok). He summons a bunch of needles and then charges forward with them, Psycho Crusher-style. At the end of the move he does one of several different random poses, just like the GG2 version.
Raven's new theme is currently titled "Tsuki no Shida" (月の虐), which means something like "The Moon's Dominance." It has vocals.
In his intro, a crow is perched on a branch in front of a blood moon, preening its feathers. The camera zooms in until its eye (which has a gold coin instead of a pupil and iris) fills the screen, then zooms back out to reveal that the eye belongs to Raven, who is now floating in front of the moon in a "bird of prey" pose. He starts to spin around, then quickly flies off the screen, leaving behind fluttering black feathers.
In his win pose, the blood moon is in the background and he's hunched over in the foreground. He slowly rises, then throws his head back and says his win quote, before leaping up and transforming into a four ravens that fly towards the moon.
In the cinematic for his IK, Sehnsucht (Yearning), he slowly walks towards the enemy while his silhouette is enveloped by an aura of purple flames, leaving only his eyes and grin visible. He grabs them by the throat and lifts them into the air, then his eyes and smile turn red and energy starts to radiate from his left eye. The energy erupts around them, disintegrating them both completely. Nothing is left but a pile of smoking ash, which Raven's regenerating arm suddenly reaches out of.
