Okay, lets get this started! I'll use numbers on each of your paragraphs.
1- 3 Tomoe can't predict what isn't there yet, sure, but don't compare Part 1 Sasuke's reaction speed to Kakashi's, Kakashi can react to a susano arrow, if enma gets out of the stick he would be on time to react. Kakashi's reaction time is heavens above sasuke's.
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2- There's no need for kakashi to "block" enma, he can just dodge it, jump back or anything, Kakashi's speed is enough to keep up with v2 jins, if he reacts to enma he can dodge him. Also, Kakashi has feats of tanking a straight atack of v2 jins like here, if he can dodge the atack or just get far enough to not get a fully directed hit from enma, he would be fine.
So yeah, Kakashi can react to enma and then dodge it, and it doesn't matter if he doesn't fully dodge the atack, he just need to don't get a full punch.
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3- Okay, let's talk about the difference of battle speed and longe distance speed... Hiruzen can cover longe distance with sunshin pretty fast, but he has no feats of being fast on a battle. If Hiruzen and Kakashi were to make a race, Hiruzen would win, big deal, on a battle Kakashi moves faster. Look at this:
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Look at the second scan, it clearly shows that Gai is facing the 6 tails by himself (fully Bijuu mode) While Kakashi is facing 4 v2 jinjurickis... Keeping up and speedblitzing 4 v2 jinjurickis like that is a feat that Hiruzen can't get.
So Kakashi can perfectly keep up with Hiruzen with speed and i'd say outlast him, while Hiruzen has good long travelling speed feats, his speed feats on the battlefield are not that impressive like against Orochimaru.
4- I already gave scans with enough proof about Kakashi being able to react to enma, His reaction speed and foot speed are enough to react to him and dodge him. Also, kakashi can make clone feints to distract Hiruzen and enma and then atack on the back.
Kakashi is an expert on clone feints, he can definitely trick Hiruzen with one of them
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5- Lol if you think Hiruzen's clone faints feats are better than Kakashi's. Hiruzen stamina is the one that's shitty here, Kakashi on the war arc already showed his stamina is about average.
6- Kakashi has counters to all atacks, hiding like a mole is a deffence trick to avoid any elemental atack Hiruzen has, and then Kakashi can use long range and nno doubt it will work
This atack would numb enma is he tries to block it, lightining spreads trough the body, Hiruzen would also get the shock
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So:
Hiruzen is slower (battle speed) , Kakashi is definitely better with clones, has more stamina, can counter all Hiruzen elemental atacks by going underground, Can react to enma and dodge him and at the end he could finish Hiruzen when he is out of stamina.