Well, the Journey Girls like Callie, Kelsey, and Meredith are often the main characters. Callie might be the adventurous one, always ready to explore new places. Kelsey could be the more artistic type, seeing beauty in everything around her. Meredith might be the brainy girl, solving problems and coming up with great ideas in the stories.
Since I don't know the exact 'Cadiz girls stories', it's hard to say. But likely the main characters would be the girls from Cadiz themselves.
Well, in addition to those, Sunset Shimmer is a very important character. She has a complex backstory, starting as a bit of a villain but then evolving into a more positive figure. Applejack is another main character, representing honesty and hard work. These characters each bring their own personalities and abilities to the stories, and their interactions are what make the Equestria Girls Stories so interesting.
The main characters in 'Code Girls Stories' are likely to be those female coders who had remarkable experiences in the coding world. They could be from different backgrounds but all had a passion for coding and made their mark in the field.
The main characters are of course the Dana girls themselves.
I'm not entirely sure as it could vary, but it might include some of the popular Girls Frontline characters who are given roles in the cafe setting.
Since we don't have the specific details of the book, it's likely that the main characters are the 'dead girls' themselves. They would be central to the stories as the title implies.
Cammie Morgan is one of the main characters. She's a Gallagher girl with great skills in espionage.
The main characters in the Lowell Girls Stories were, of course, the Lowell girls themselves. These were young, mostly unmarried women who came to work in the Lowell mills. They were from different rural backgrounds and brought with them their own values and dreams.
There are many main characters as it features a variety of women. It could include female leaders like Malala Yousafzai, who fought for girls' education.
I'm not sure exactly as I haven't read it in detail, but likely there are female characters who are at the center of the stories, perhaps some young girls dealing with the situation of war.