Zabuza vs Darui
Location - Grassy field with lake available
Knowledge - Darui knows Zabuza's the best at Silent Killing and Zabuza knows of Darui's Black Lightning because of his tattoo.
Restrictions - Darui can't use Double Black Panther and Shadow Clone Jutsu because they are uncannon.
Even though Darui is probably the stronger ninja overall of the 2, I think Zabuza can beat him because Darui has no way of finding and sensing Zabuza in the mist. as you can see in this manga image, Kakashi possessing a 3 tomoe Sharingan was getting hit by Zabuza even before his eye was numbing, so Darui, without a Sharingan and no enhanced sensing abilities like Kakashi's hound dogs has no way of keeping up with Zabuza.
The only way I see Darui winning is if they are battling on water and Darui jumps up and uses Black Lightning on it to shock Zabuza, however none of Zabuza's battles were fought standing on water, just water available to the side. So even if there's no water available Zabuza can still use Hidden Mist Jutsu, as shown in the Fourth Shinobi World War, and then use Silent Killing against him.
Even if somehow Darui can react to Zabuza, Zabuza can use Water Clone feints and Water Prison on him, if a 3 tomoe Sharingan Kakashi couldn't keep up with that, then Darui can't.
Also some of you will say Darui could use Laser Circus before Zabuza put's up the mist, well no, Zabuza puts up the mist way to fast, as you can see here, Zabuza put up the mist in a couple seconds standing not even 5 feet from Kakashi, You don't think Zabuza can put up the mist even when he did against over 15,000 shinobi? get some common sense here, he put it up even with Guy around, and Darui's speed doesn't compare to Guy's.
A lot of you will say Darui can cancel out Zabuza's Water Dragon and Giant Vortex with his lightning, how the hell does he do that haha, if Zabuza uses Giant Vortex Jutsu and if Darui infuses lightning in this, it won't cancel it out... it'll make it even stronger because lightning increases the power of suiton techs, so Darui will get hit with even more fire power.
Also, Zabuza is better at taijutsu then Darui, even though Darui runs lightning through his blade, it wont completely cut the executioner blade in half, as shown when Darui faced Suigetsu with it and when Sasuke used his blade against Killer B with the executioner. Also the blade can rebuild itself.
Oh and a lot of u will say Darui is to skilled to die from silent killing, well, why do u think his silent killing and mist were so well known and feared throughout the ninja world? if u dont have sensing abilities or a jutsu to navigate it, which Darui doesn't, ur screwed.
Sorry for typing all that shit haha but you know just trying to make a very well put argument, because a lot of u know me as a huge Zabuza fan.
Thoughts? btw this is just my opinion, dont hate