@Monkey:
Same place as Big Mom's.
Off screen and panel until we get to a point where Oda shows them.We were introduced to members of the Redhair pirates in chapter one lol.
Sorry if I didn't make myself clear, I basically meant we haven't seen any Red-haired pirates since the second half of One Piece. I'm sure they'll make an appearance sometime in the Yonko saga, but one would think one of the strongest crews in the world would be a little more popular in the new world so far. I guess they're not the focus right now, but with characters like Ben Beckman, Lucky Roo, and other interesting crew members barely getting panel time I'm beginning to get a little impatient lol.
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Thing is, from a story point of view, Oda only shows things that are plot-relevant, and Shanks' crew are too nice (to the Straw Hats) to be of any importance thus far. They will come up, though, don't worry.
From an in-world point of view, although the Yonkou dominate the New World, the Straw Hats have only been to 4 islands thus far - and that is counting Zou which was under no Yonkou's jurisdiction. You can't really expect to have seen all 4 Yonkou by that point. The Straw Hats have mainly moved through the territory of Kaidou, and after the run-in with Big Mom's ship their path was diverted to her territory as well. And they saw Burgess in Dressrosa, only because of the tournament. We haven't even reached the halfway point, even after skipping the first set of islands. Having met with the crew of 3 Yonkou is just about right, if not already impressive.
It doesn't have to indicate that Shanks' forces are any less than the others; it just means they haven't gotten to any territory where he has business.
Yeah, I wonder where Shanks' territory is, how much it is, and if other Yonkos a la Blackbeard are constantly trying to take it. It'll be interesting to find out.