Captain Megumi and Director Sawai from the movie appeared in the movie because they were important characters in the Gauss Ultraman series and were extremely famous and popular.
Captain Hui was one of the important characters in the original comic and animation of Ultraman. He was the captain and combat expert of Ultraman. He was known for his superb technical and tactical abilities and had always protected the Earth from various threats. In the movie version, he participated in the final battle against the evil monster and played an important role.
Director Sawai was another important character in the Gauss Ultraman series and one of the producers of Gauss Ultraman. He was responsible for the planning and production of the Gauss Ultraman series and also played an important role in the game. In the movie version, he participated in the final battle against the evil monsters and provided important strategic advice and technical support.
The appearance of Captain Megumi and Director Sawai in the movie was one of the important plots in the Gauss Ultraman series, and it was also a re-demonstration of their important roles. Their appearance not only increased the movie's storyline and enjoyment, but also increased the audience's attention and love for the Gauss Ultraman series.
Sukuna does die in the manga. The way it happens is quite dramatic and ties in with many other elements of the story, adding depth and tension to the overall narrative.
As of the latest chapters I've read, Megumi is still alive in the manga. Usually, such major character deaths are significant plot points and would be well-publicized if they occurred.
No. Ryomen Sukuna is a fictional character from Japanese mythology and modern manga/anime. He doesn't have a basis in a true historical event or person.
Nope. Ryomen Sukuna has no basis in reality. It's a product of the creative minds of the writers and illustrators who designed a captivating fictional character for the enjoyment of the audience.