Roronoa Zoro is one of the strongest members of the Straw Hat Pirates. He joined the crew after Luffy saved his life. Zoro is a very ambitious person and he dreams of becoming the strongest swordsman in the world.
Zoro's path is not easy and he has got a lot of tough opponents ahead. He received Enma at Wano, which is a big boost for him. Zoro hasn't gone all out yet in Wano and the fans can't wait to see how strong Zoro is.
10 STRONGER: PORTGAS D. ACE
Portgas D. Ace is a Supernova from the old generation. Ace set out to make a name for himself when he was still very young. Ace's reputation grew at an alarming rate and in order to curtail his growth the World Government offered him the position of a Shichibukai, however, his goals stretched beyond being just a Shichibukai.
Ace's Fire Fist was enough to destroy an entire town, and there is no way that Zoro could stand up to someone like Ace.
9 WEAKER: KILLER
Killer is the right-hand man of Eustass Kid. He is the only person that Kid trusts. When Basil Hawkins accepted Kaido's offer to join him, Kid and Killer fought the Yonko.
Killer has got a great reputation, but he hasn't done anything outstanding. Also, he actually fought Zoro at Wano, and lost; but both of them were weakened.
8 STRONGER: EUSTASS KID
Eustass Kid has been closely observed by the fans ever since his introduction at Wano. Kid was captured by Kaido after Apoo ratted them out.
Kid has some impressive feats so far; the best being that he managed to injure a Sweet Commander. Kid is merciless and his reputation is that of a notorious pirate. Roronoa Zoro would be at a big disadvantage due to Kid's devil fruit power.
7 WEAKER: CAVENDISH
Cavendish is the captain of the Beautiful Pirates. He is one of the few pirates who are despite having no devil fruit. Cavendish is a threat to everyone including his own crew when his alter ego, Hakuba takes over his body.
Cavendish's speed and power are impressive, which cemented his reputation as a Super Rookie, but Zoro is on a higher level than him.
6 STRONGER: MONKEY D. LUFFY
Next up on the list is Monkey D. Luffy. He is the captain of the Straw Hat Pirates. He is the strongest person in the crew and there is no doubt about it. Luffy has some insane feats to his name.
He has single-handedly taken down the likes of Charlotte Cracker, Doflamingo, and Katakuri. Luffy can use all three types of Haki and his enhanced control over his devil fruit makes him an extremely tough opponent.
5 WEAKER: BARTOLOMEO
Bartolomeo is undoubtedly the biggest fan of the Straw Hat Pirates. He would readily sacrifice his own life in order to save the Straw Hats. Bartolomeo's devil fruit is a huge problem for his opponents.
The barriers that he erects can withstand every attack, but it is still unknown whether or not it can withstand attacks coated in Haki. Since Zoro specializes in Armament Haki, he should have no trouble overcoming this barrier.
4 STRONGER: TRAFALGAR LAW
Trafalgar Law is the captain of the Heart Pirates. During the time-skip when Luffy and his crew were training, Law was focused on enhancing his own reputation. He did so marvelously as he managed to become a Shichibukai. Law's devil fruit- Ope Ope no Mi is arguably the strongest devil fruit in the series.
The devil fruit can even bypass Haki along with several other abilities. In a fight between Zoro and Law, the former would be lucky if he was still in one piece.
3 WEAKER: BASIL HAWKINS
Basil Hawkins joined Kaido's pirate group because he knew the chances of him surviving otherwise were pretty slim. Hawkins' fought against Zoro at Wano and it was a very close fight.
Hawkins's devil fruit allowed him several opportunities to try different tactics. Since that fight, Zoro has gained Enma, which is an O-Wazamono sword that was wielded by Kozuki Oden. If another fight between the two was to break out, then Zoro would be triumphant.
2 STRONGER: CAPONE BEGE
Capone Bege is the captain of the Fire Tank Pirates. Bege's devil fruit is quite awesome, it makes him a walking fortress. His ultimate weapon is "Big Father," where he turns into a giant fortress that is equipped with cannons and other weapons.
This form of Bege is quite tanky and it can withstand a lot of hits. Zoro would have a really hard time with Bege as he fights using both his wit and devil fruit.
1 WEAKER: CARIBOU
Finally, we have Caribou, the co-captain of the Caribou Pirates. He was first introduced at Sabaody Archipelago after the time-skip. Despite his looks, Caribou is a very cunning and powerful opponent. He gained notoriety for killing several Marines. He was also an antagonist in the Fish-Man Island arc.
Later on, he was captured by X-Drake and sent to Udon prison. There's really no comparison between Zoro and Caribou, the former is light years ahead.
