Much to the chagrin of some fans, the second season of the wildly popular One Punch Man was handled not by Madhouse, but by J.C. Staff. While this studio swap has made headlines, it's not the first time that such a thing has happened. In fact, there are plenty of anime that switched studios at some point during the development process. Often, this takes place between seasons, or before a reboot.
Why would a property being managed by one studio move to another? Reasons vary, but they tend to involve logistical issues rather than anything especially dramatic. Anime studios typically don't own the rights to the anime they produce - typically, they work as contractors and must bid to take charge of a desirable property. Sometimes it's because the studio simply doesn't have the time or manpower to take on a sequel series, or because the director had a change of heart. In some cases, as with the Fruits Basket reboot, it's because the author of the manga that the anime was based on was dissatisfied with the first attempt and wanted the new series tackled by a new staff.
In some cases, a studio change can feel like a downgrade - that's definitely true of Psycho Pass, which decreased dramatically in quality when it moved from Production I.G. to Tatsunoko Production. But at other times, like with Fate/stay Night's swap from Studio Deen to ufotable, the changes are for the better. Sometimes, the change hardly seems to make a difference. No matter how the change impacted the series itself, it's still interesting to know about the show's production history.
Almost every season of Yu-Gi-Oh! has been handled by Studio Gallop - except for one. Toei Animation actually had the first shot at adapting the manga, but their attempt, now referred to as Season 0, was canceled after 27 episodes because the adaptation was not well-received by Japanese fans at the time. Studio Gallop restarted the series with a new anime called Yu-Gi-Oh! Duel Monsters, which is the series that most fans are familiar with.
While Duel Monsters did tell a complete story, it left out the violence that Season 0 covered. Yu-Gi-Oh! was originally intended to be a horror manga with game elements, but eventually became focused on a single game, Duel Monsters. The new anime picked up where the manga started to be about the game in question, while Season 0 covered some of the more brutal assaults committed by the ancient Egyptian spirit. Whether or not this change is a good thing depends on the viewer.
The first season of the wildly popular One Punch Man was handled by Madhouse, one of the the best studios in the industry. In its second season, J.C. Staff took over the production. The directors also changed hands, with Shingo Natsume directing the first season and Chikara Sakurai directing the second. The reason for the change was never officially disclosed.
While it's too early to say whether this change will ultimately be for better or worse, the second season looks less than promising. This is mainly because of the dip in art and animation quality - it just doesn't look as sharp. This could be okay with a different series that hadn't already set such a high standard, but for a high-quality show like One Punch Man, it's disappointing to say the least. Maybe J.C. Staff will pull through and create a worthwhile sequel, but right now it seems like it was better off in Madhouse's hands.
The first season of Psycho-Pass was made by Production I.G., a studio known for high-quality shows like Haikyuu!! and Eden of the East. Tatsunoko Productions took over the production of the second season. This move made sense because Production I.G. was originally a subsidiary of Tatsunoko Productions, and the two companies still had a business relationship. The change may also have been influenced by the fact that even in the first season, the team was so exhausted and overworked that they had to contract episodes 17-18 out to another studio, resulting in lower quality than usual and forcing them to eventually remake the episodes.
Nevertheless, this change was not for the better. The animation quality remained relatively stable, but the story itself took a nosedive. The second season, which was written by Tow Ubukata, who took over for Gen Urobuchi, was poorly constructed and didn't remember its own rules. For example, Kamui, the main villain, was supposed to be composed of bodies parts from all of the victims of an accident he was in, rendering him unreadable by the scanners that determine everything in this world. If he was unreadable, he wouldn't have been able to successfully blend into society as he had. Characterization was also thin - Shimotsuki's arc was simply an unsatisfactory rehash of Ginoza's.
Would Production I.G have done a better job? Hard to say - but the quality definitely changed between the two series.
The new Fruits Basket is a reboot, not a sequel - but it's not uncommon for reboots to be handled by the same studio who took on the original. Although it had its own charms, the 2001 Fruits Basket anime, which was produced by Studio Deen, failed to successfully adapt Natsuki Takaya's manga. It only covered the first few volumes of the manga, and it ended on a note that made future manga developments logically impossible. Natsuki Takaya repeatedly clashed with Studio Deen's director Akitaro Daichi on details like the coloring, the cast, the storytelling style, and more.
For this and other reasons, Takaya said this about the remake: "I made several requests right off the bat. One of those was to do it with a completely new team. Completely new. Every single person. I told [the producers], if you want to open the curtain again, then please make it all new. Please rebuild the Furuba world from scratch, with new everything." As a result, the 2019 reboot was handled by TMS Entertainment, and none of the old voice actors, writers, or anything else returned. However, the dub cast remained the same.
The reboot will cover the full scope of the manga's story, revealing secrets about the curse, introducing new characters, and solving romantic questions. Time will tell how well TMS Entertainment will handle it, but so far the new series is artistically and aesthetically superior to the original.