The Red Hair Pirates are led by Shanks, who is one of the Yonko. Shanks is more or less an enigma and the fans can't help but wonder when Oda will finally reveal something about him.
There is very little information about the Red Hair Pirates, apart from the fact that they're pretty strong. So far, we have seen that a lot of Supernovas have joined up with other Yonko, in order to boost their reputation as well as increase the strength of the Yonko.
10 WOULDN'T: EUSTASS KID
Kid is one of the many Supernovas who are currently in the Land of Wano. He had originally formulated a plan to take down Shanks with the help of Scratchmen Apoo and Basil Hawkins. Prior to forming the alliance, Kid had fought against Shanks' crew resulting in him losing his left arm. There is no chance that Kid would join the crew of the person who took his arm.
9 WOULD: MARCO
Marco is one of the most well-known pirates and was approached by Shanks several times in an attempt to make him join the Red Hair Pirates. At that time, Marco was obviously loyal to Whitebeard and no amount of wealth would make him leave the crew. But, now things are different. Marco lost his father and after that, he lost the Payback War versus the Blackbeard Pirates. Shanks could convince him to join his crew now.
8 WOULDN'T: CAVENDISH
Cavendish is the captain of the Beautiful Pirates and is one of the Super Rookies. Cavendish was one of the many participants at the Corrida Coliseum.
Cavendish is an expert swordsman and would make a great addition to any crew. However, he is very haughty and he won't be willing to join the Red Hair Pirates readily.
7 WOULD: BUGGY
After the death of their captain, Gol D. Roger, Shanks and Buggy went their separate ways, however, before starting their own crews, Shanks asked Buggy to join his crew. But, Buggy turned him down straight away, though Shanks and Buggy are still very good friends. This could actually be a good time for Buggy to join Shanks' crew because the Shichibukai system has been abolished and now, with the truth about Buggy's past out, the World Government will no doubt try to capture him.
6 WOULDN'T: BARTOLOMEO
Bartolomeo is arguably the biggest Luffy fan. He absolutely adores Luffy and his crew, which is why Bartolomeo follows everything they tell him to do. But, this is only limited to the Straw Hats, while talking to other people, Bartolomeo usually talks in a condescending tone. During the Dressrosa arc, it became perfectly clear that he would not obey anyone else.
5 WOULD: DRACULE MIHAWK
Dracule Mihawk is the Strongest Swordsman in the World. Mihawk used to be a Shichibukai but after the dissolution of the system, he is just another notorious pirate. He used to be rivals with Shanks and their duels are considered legendary.
Mihawk and Shanks have a lot of mutual respect for each other. A lot of theories actually suggest that Mihawk might actually be a member of the Red Hair Pirates.
4 WOULDN'T: BOA HANCOCK
Boa Hancock is known as the Pirate Empress. She amassed a bounty of over 50 million beris from her first voyage; the World Government immediately acknowledged the threat and offered her to become one of the Shichibukai. She accepted as it would ensure the safety of Amazon Lily. So far Boa has shown that she would only obey Luffy, so expecting her to obey Shanks would be a mistake.
3 WOULD: CROCODILE
Crocodile is one of the most mysterious characters in the series. He possesses the Suna Suna no Mi, which is a logia type devil fruit. In the past, Crocodile declined the offer to work with Doflamingo, however, he has shown that he can team up with people if the situation demands. If he were to join the Red Hair Pirates, he would definitely get a chance to learn about some of the darkest secrets in the world.
2 WOULDN'T: KING
King is the right-hand man of Yonko, Kaido. He possesses Ryu Ryu no Mi, Model; Pteranodon, which is one of the few flying type zoans. King is very loyal to Kaido and he isn't willing to join the crew of any other Yonko. In fact, Big Mom personally asked King to join her crew, but he declined the offer straight away. So, it wouldn't make sense for him to turn down one Yonko and join another.
1 WOULD: JEWELRY BONNEY
Jewelry Bonney is one of the members of the Worst Generation. She possesses an unnamed devil fruit that enables her to alter the age of anyone she touches. According to several theories, the devil fruit might be the reason why the World Government is chasing her. Bonney has had to stay discreet so that the World Government doesn't get an opportunity to catch her. It would make sense if Bonney joined the crew of a Yonko to seek protection.
