<p>I seriously doubt Orochimaru is fast enough to catch Minato when Ay couldn't do it.
</p><p>The only person to ever catch an FTG user was Madara in Sage Mode or as the Ten-Tails' Jinchuuriki, both instances rather a feat of reaction time than raw physical speed, both respectively boosted by his higher forms.
</p><p>SM Naruto could dodge the Third Raikage's attack in Sage Mode, and the latter was much faster than Naruto. However in the same vein, Jugo while in Sage Transformation, could barely react to the 3rd Raikage.
</p><p>Minato doesn't really have anything in his arsenal to kill Orochimaru, and Orochimaru wouldn't be able to catch Minato.
</p><p>Since OP never mentioned about anybody needing to actually die to win, I would go with Minato. Orochimaru would just get BFR'ed pretty fast.
</p><p>Also, Sword of Kusanagi is an inanimate object. It doesn't have any speed feats. That was Oro's tongue. His tongue blitzed Kurama.
</p><p>Enma hitting Kurama isn't really a feat, random shinobi could hit him with explosive tags. Tailed Beasts aren't really known for speed.
</p><p>The God Tree was more of an immovable object, so blitzing that isn't really a feat as well...
</p><p>In a battle to the death, however, Orochimaru would win. Simply because of the fact that he cannot die.
</p><p>Minato using the Reaper Death Seal is not really a win either, both of them die, so that's a stalemate.
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