Ideally who you would want to be in charge of the anime? I feel like we would all agree that Production I.G doing a two cour anime adaptation and possibly more in the future would be the best choice.
Then Madhouse would probably be a good pick despite them being a shell of their former selves. But, they did do the rugby All Out anime recently with TMS Entertainment and they seem to have handled it decently enough, you know, that also had buff guys wrestling it out in dirt xD. TMS Entertainment would probably also work out.
Ideally, the miracle scenario would be for the anime to air in Fall 2018, after My Hero Academia season 3 finishes airing if it has two cours again. That TV block would be fantastic for HZ and the anime would run for two cours until April 2019, after Production I.G finishes the first season xD.
But, in reality I feel like we're going to get Toei, because they did do a reboot of one of their classic anime series in 2014, which was an adaptation of a very old sumo manga and I think Toei are really the only studio that really made any sumo anime in general.
If we get lucky, the show will get a pretty good staff like the Tiger Mask W got, I heard the reboot was quite awesome and had a lot of great highlights.
I mean, this usually isn't something I'd consider a benefit, but it would probably get a 48-50 episode run to the minimum and that would probably be enough to cover the first part of the manga more or less, since there is a lot of material to work with, but it depends when the planning for the anime started... I'm not fully caught up with the manga, so if you think the first part of the manga can be covered in less episodes, you can give your opinion, I'm not sure how the manga's pacing would translate into an anime.
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