Summary
- The new opening and ending theme songs for the Egghead Island arc in One Piece will be performed by Hiroshi Kitadani and Maki Otsuki, who have previous experience with the series.
- Speculation suggests that Hiroshi Kitadani's song "A--su!" will be an energetic rock song, while Maki Otsuki's song "Dear Sunrise" will be a more mellow piece.
- The choice of theme songs is expected to enhance the excitement and emotional impact of One Piece's final saga in the anime adaptation.
In January 2024, One Piece's anime will officially begin adapting the Egghead Island arc, meaning that just like the manga, the One Piece anime will have entered its final saga. Going right along with that, the anime will receive a new opening and ending theme song: Hiroshi Kitadani’s "A--su!" and Maki Otsuki's "Dear Sunrise", respectively.
New theme songs for a new arc is a common practice for anime, and the specific artists chosen for One Piece are a perfect fit for the Egghead Island arc. As previously discussed, the Egghead Island arc kickstarts One Piece’s final saga, and since Hiroshi Kitadani and Maki Otsuki sang the original opening and ending themes for One Piece, bringing them back for the Egghead Island arc serves as a perfect bookend for the anime as it enters its final saga.
It's unknown how the new theme songs will play out, but considering the overall talent of the artists in question, they'll undoubtedly be perfectly fitting for One Piece’s anime.

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One Piece's Latest Artists Have Plenty Of Experience With the Anime
Created by Toei Animation, based on the original manga by Eiichiro Oda
Even without counting the original opening and ending theme songs, Hiroshi Kitadani and Maki Otsuki both have plenty of experience contributing to One Piece. In addition to "We Are!" and "Memories", Maki Otsuki sang "Destiny" for One Piece: Heart of Gold, and Hiroshi Kitadani has performed the 15th, 19th, and 22nd One Piece openings, "We Go!", "We Can!", and "Over the top", respectively. Both artists have plenty of experience with providing great music for One Piece even beyond singing the original opening and ending theme songs, and that experience is sure to lead to even greater performances for the themes.

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What Will One Piece’s New Theme Songs Be Like?
With Hiroshi Kitadan and Maki Otsuki performing the next opening and ending themes for One Piece, something else to think about is what sort of songs they'll be contributing. Considering the titles of the songs and their past work both in and out of the franchise, Hiroshi Kitadani's "A--su!" will likely be an energetic rock song to kick off each episode, while Maki Otsuki's "Dear Sunrise" will be a more mellow piece to serve as denouement. Both styles of songs have shown up plenty of times in One Piece over the years, so it would make sense for "A--su!" and "Dear Sunrise" to fall into a similar pattern.
Naturally, anything about the theme songs is purely speculation, but that sort of pattern would be more than appropriate. With the Egghead Island arc, the first arc of One Piece's final saga, it warrants an opening theme that gets people excited about One Piece entering its final stages and an ending theme that calms things down after every crazy event, and Hiroshi Kitadani and Maki Otsuki are the perfect people to do all of that just like they did 25 years ago. One Piece's final saga is going to be even bigger in the anime, and the anime's choice of theme songs will surely play a big part in that.
Source: Anime News Network.