About Enma and Oden being able to control it as a child.
I have my own answer to that which I will explain in two point.
-First the sword isnt cursed and nothing happened to it after Oden used it and dead.
its just that Enma is a sword that has his standard.
Oden received Enma as a child and grew up with it obviously his control over it will be better than someone who was using wooden sword to train prior to getting Wado Ichimoji or using a sword like Sandai Kitetsuu that is of lower rank compared to Enma.
Just think of all the sword zoro used as a training tools, Enma is S tier training tool, Wano Ichimoji A tier and kitetsu B tier.
You wont get the same reult using a B or A rank training tool compared to an S rank.
-Second Enma need extreme coa release something Oden learned as a child and perfected while growing UP, Oden was using Enma Ever since he was born so he learned earlier how that satisfy it by going all out (unlike Zoro who restreint), this made Oden someone who while growing UP had no problem using huge amount of haki all time UNLIKE Zoro who developed the oposite habit which is to hold back his haki and power cause so far none of his sword( remember training tool) needed him to always go all out.
This oposite habit was what made it didficult for Zoro to control Enma despide having greater haki and much more will power than Oden himself.
Rooftop Zoro despide matching Oden's Legendary feat and unlocking CoC still couldnt control Enma like Oden who unlike him didnt had CoC when fighting Roger.
But the moment he finaly understand Enma's test he did it, not only matching prime Oden haki output but surpasing it by releasing so much CoA , his sword turn into fire.
Ohk first. Blade was always cursed , swords choose their owners.
Oden was the first wielder of Enma and Enma choose him.
Like Sandai choose Zoro but has killed a lot in past.
Enma was absolutely foreign to Zoro and they way he uses Haki. Mihawk only taught him how to coat one with armament Haki not the continuous Flow. We have never seen Zoro struggle with Haki because all the fights so far he just coated them. Never thought putting more (In short he never went all out)
Same with Shusui , Shusui Choose Zoro after he beat ryuma zombie in a fair battle. Earning the right to use it.
And I agree with the rest. Zoro already surpassed oden on Rooftop by just doing what Oden did with Adcoc and Zoro only used Ryou with Ashura , Healthy Zoro would have given similar result to Oden. (also Zoro never used all of haki , He never complained on his Haki on rooftop it was his body which gave up due to broken bones). And on how strong Zoro Haki is ?
Let's go back to What mihawk Taught him , a Black blade never breaks. Zoro only used Ryou and Armament against Kaido and King for defense. And was able to keep up with them.
With Ryou , he learnt to go all out and when he did we saw KoH types of things around.
Unlike Luffy who goes on cooldown , Zoro never bothered with cooldown Stuff.
