What happened to Rokka no Yuusha?

In 2015, the only season of the fantasy adventure series "Rokka no Yuusha – Braves of the Six Flowers" aired in Japan and internationally on Crunchyroll. The anime, based on a light novel series by Ishio Yamagata, uniquely incorporates a mystery narrative into an action-fantasy series about heroes and demons.
"Rokka no Yuusha – Braves of the Six Flowers" gained popularity among international audiences, but the end of the first season was left open and fans have been wondering if there will be a second season for almost a decade.

The story centers on the legend of the Six Flowers. A thousand years ago, a being known as the Demon God attacked every nation on earth. The Demon God plans to seize power with demons and wreak havoc on the lives of humans, but the One Flower Saint was able to stop this disaster by sealing it. However, as the seal is temporary, the Saint prophesied that six "brave" or warriors will be chosen to protect the lands and re-seal the Demon God when he appears again.
The first and second generations of brave men were able to do their duty. However, the third generation faced unexpected circumstances: two more brave people joined the team. In the "Rokka no Yuusha – Braves of the Six Flowers" anime, the seven brave men are trapped by accidentally activating the fog barrier surrounding a temple. While they're trapped, they must figure out who the brave imposter is. At the end of the first season, the brave have unmasked the traitor and continue their journey to stop the Demon God alongside another brave new one.

So far there are six volumes of the light novel and one spin-off volume of "Rokka no Yuusha – Braves of the Six Flowers". Unfortunately, there hasn't been any news or update on when author Ishio Yamagata will continue the series, which has been on an indefinite hiatus since 2015. Fans have noted that Yamagata takes his time when it comes to writing: each volume of this novel took about a year to publish.
Although the source material is there, there have been no moves for a new season of the anime yet, and fans can only speculate on the reason. The first possible reason is that "Rokka no Yuusha – Braves of the Six Flowers" did not attract many viewers in Japan despite its popularity among international audiences. The second is that the Japanese studio, Passione, was fairly new to anime when this series was in production, with only two other series produced under its belt.
Now that he's made a name for himself, Passione surely has no intentions of picking up the "Rokka no Yuusha" project for a second season, as the first season was unsuccessful in Japan. Still, we are in a time where many series from almost ten years ago are receiving continuations, will it be the turn of this franchise?
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