Now I'll finally state my points. I decide all my battles using a 10 Edge System, character with most advantages will most likely win.
Intelligence: Who is the smarter combatant, tactician, and overall has more knowledge in fighting and more? Tchalla-
Super Genius who has knowledge in technology and magic, leader of the world's most advanced civilization, has lead them to many victories.
Experience: Who has battled and defeated more things, aswell as a number of different threats? Tchalla-
Yes, Geralt is close to 100 years old; and yes he's hunted, battled, and defeated a number of things: Vampires, Werewolves, Strigas, Dragons, and more.
Yet Panther has faced most of those things and threats Geralt has never come across: Doom, Namor, Black Dwarf, Vampires, Werewolves, Advanced Aliens, Robots, etc. Further as already mentioned, Tchalla has the knowledge of every Black Panther past, that's over a 1,000 years of knowledge.
Skill: Who has superior Martial/Hand To Hand knowledge, training, and more of the sort? Tchalla-
Yes, Witchers are masters of pretty much every melee/hand to hand weapon, so Geralt is definitely no slouch. However, Panther has studied every fighting style known to man, created 3 of his own unique styles that incorporates mysticism. Further Geralt has never faced combatants like Taskmaster, Wolverine, Cap and more. Wolverine has more experience than Geralt, being over 100 years old, and Tchalla has routinely gotten the upperhand on him- it wouldn't be any different with Geralt. Overall Tchalla has and knows more skills, and has regularly battled opponents with highly levels of skill, whereas Witchers more so routinely battle monsters.
Strength: Tchalla-
Yes, both are superhumans. However, Panther has specifically been shown and stated to handle 5 tons, lift over a ton, and he's only gotten stronger overtime. Geralt doesn't have much that shows exactly his physical level. He's done some impressive things though.
Speed: Tchalla-
Superior strength usually goes into superior speed, but not always in comics. Overall Panther has more and superior speed feats; he's literally disappeared in front of people, is stated to be faster than a panther, dodged bullets at point blank range..etc.
Durability: Who can endure more damage? Tchalla-
Geralt does have a healing abilities, but not on Panther's level. He's just recently survived being impaled- apparently being King of The Dead keeps from dying.
Invulnerability: Who has superior resistance to damage? Geralt-
Without the Vibranium suit, and Geralt having the ability with his Magic Sign Quen to cover his body in a magical shield, he surely takes this edge. However, Tchalla, even without his Vibranium suit has shown to have an energy shield...
However as you can see, it can break- but so can Witcher's Quen. Too, there isnt much guarantee Tchalla has such available, since he hasn't shown it in a few years.
Weaponry/Equipment: Tchalla(slight)-
There is a common misconception that if Panther doesn't have his suit, he has none of his other equipment and tech, even some writers has shown this...but such is not the case. Geralt has swords, explosives, potions, and magical signs; yet even without his suit Panther still has Energy Daggers, Spear Of Bashenga, which both can be explosives and cut through anything. Overall he has the superior gear.
Versatility: Geralt (Slight)-
With his magical signs, Tchalla having less of his equipment available, and thus being more vulnerable, Geralt has more going for him in this fight.
-Igni & Yrden have been taken away for this fight to make the match more fair sense Tchalla's has been taken away.
-Aard, Telekinetic Force Push. Tchalla has no real way to counter, but he can evade it.
-Axxi, Mind Control. Yet Tchalla has a high level of psionic resistance, so he'll be able to overcome it or repel it.
-Heliotrope, magical barrier to protect from harm.
Range: Geralt (Slight)-
Superior range attacks.
So Tchalla has 7 to 3 out of 10, he has more edges. He'll take the victory after a long and hard fight in my opinion. Geralt's signs are the only thing that will make the battle tough. Most of the things Geralt has defeated he's had prep time which he uses special things to exploit their weaknesses. He won't be able to do that here. I'm not saying Geralt has never defeated anything major without prep, just saying that's what normally helps him be successful. So Tchalla wins in my opinion, even without Vibranium suit.