Naruto:
• AP advantage
• Durability Negation, via Rasenshuriken
• Frog Kata, which negates Precognition
• Clones of comparable strength
• Range advantage
• Genjutsu with Ma & Pa
• Summoning
Yami:
• Accelerated Development through battle
• Durability Negation, via Dimension Slash
• Paralysis & Absorption with Black Hole
• Barriers of Dark Magic
• Precognition that senses muscle movement, intent, breath, emotional states
• Increased stats with Reinforcement Magic + Mana Skin
Yami by no means starts with Dimension Slash in this key, and uses it as a last result. Yami’s Ki far exceeds any Sharingan precognition, and as such Frog Kata wouldn’t be of issue. That’s assuming Naruto can get in, as Yami has no problem striking at a distance with Lightless Slash, which he can spam constantly. Summons may be a problem, but since this is War Arc SM Naruto, he doesn’t start with that, neither Ma & Pa.
Conversely, dozens of comparable duplicates are definitely a problem for Yami, and while he can dodge, he can’t do it forever. He can mitigate this by paralysis via Black Hole, and considering the sheer amount of clones Naruto can summon (in base, not SM), it may serve an issue, but that’s assuming Naruto gets forced into Base, and Yami has no way of knowing that SM
has a timelimit. Of course, the further Yami is backed into a corner, the more liable he is to break his limits (getting jumped by the Third Eye whilst weakened).
A Rasenshuriken is Yami’s biggest threat, due to AOE, but at that moment Yami will not hesitate to use Dimension Slash - and spatial severing is far more dangerous than cellular blades, and a more pressing question is if Naruto can sense that, but he has a Danger Sense.
Overall, I genuinely see this going either way. Naruto’s got a lot as his disposal, and Yami can directly counter that or hold his own with his own abilities. Inconclusive, for me.