Current Kakashi has shown much better stamina than Itachi had. This is why even if Kakashi's mastery of MS is lower than Itachi's (which is hard to determine for sure, since they have different MS abilities), he can spam Kamui more than Itachi could any of his MS techniques. Since Kamui can be used both for defence and for offence, I think Kakashi would pull it off more times than not.
If ms is restricted kakashi can win but Ms is the reason itachi is so op
Amaterasu and tsukyomi are one-shot techs
Yata blocks everything
Toska seals everything
9/10 kakashi looses to this.
But without it Kakashi's MS moveset is:
Chidori
Demonic Illusion: Hell Viewing Technique
Earth Release: Double Suicide Decapitation Technique
Earth Release: Earth-Style Wall
Earth Release: Hiding Like a Mole Technique
Eight Gates
Evil Sealing Method
Genjutsu: Sharingan
Lightning Beast Running Technique
Lightning Cutter
Lightning Release Shadow Clone
Lightning Transmission (Manga only)
Multiple Shadow Clone Technique
One Thousand Years of Death
Rasengan
Shadow Clone Technique
Silent Killing
Summoning Technique (Ninken)
Summoning: Earth Release: Tracking Fang Technique
Water Clone Technique
Water Release: Great Waterfall Technique
Water Release: Water Dragon Bullet Technique
Water Release: Water Encampment Wall
Water Release: Water Shark Bullet Technique
While itachi' is:
Clone Great Explosion
Crow Clone Technique
Demonic Illusion: Mirror Heaven and Earth Change
Demonic Illusion: Shackling Stakes Technique
Dusk Crow Genjutsu
Ephemeral
Fire Release: Great Fireball Technique
Fire Release: Phoenix Sage Fire Technique
Fire Release: Phoenix Sage Flower Nail Crimson
Genjutsu: Sharingan
Izanami (Manga only)
Shadow Clone Technique
Summoning Technique (Crows)
Water Release: Water Fang Bullet