First off, the character's personalities don't change! They are the same persons with the same character attributes - only in a different universe.

Usagi: Usagi is the Avatar and thus the one who can bend all for elements; the first element she learned to bend was earth. However, she is not able to master them at the beginning of the story. The same goes for her spiritual connection - it's more than hard for her to get into the Avatar State or to connect with her past lives. Sometimes things are getting even harder because of her clumsiness.

Ami: Ami is a waterbender living in the Northern Water Tribe. She is in great demand because of her exceptional good healing powers. Despite her young age she is already one of the best healers in her Water Tribe and is in general a good bender who bends the water smoothly and with an ease of mind. Ami often spends her time with studying and reading where she looks for new bending techniques and other interesting facts.

Rei: Rei is a firebender that comes from an average family. Most of the time she was alone and didn't have any friends. That changed when she met Makoto, a non-bender that moved to her hometown. At first she didn't get along with her but the more they talked to each other the more she liked her. With her new friend she isn't alone anymore and spends most of her time with her. They are often competing in Agni Kais for fun.
Rei has a good intuition, senses it when bad things are coming in the near future and has in general a good spirituality.

Makoto: Makoto is a non-bender that lives in the fire nation. She lost her parents when she was a child and besides her parents she had no one else. That's why Makoto had to grow up with bad living conditions, mostly on the street. Nonetheless it can't be denied that her hard life helped her to improve her fighting skills: She masters several martial arts - including the mostly unknown chi-blocking. However, due to the loss of her parents, she was all alone and had no one to spend time with. That changed when she moved to another town and eventually got introduced to a firebender called Rei. At first they didn't get along that well but later they grow dear to each other's heart. Even though Makoto is a bit disadvantaged since she is a non-bender she often competes with Rei in Agni Kais - and sometimes she even wins against her. So it's no problem for Makoto to fight a bender.

Minako: Minako is an airbender who lives in the Western Air Temple. She is not the typical kind of airbender; actually she reminds of Aang with her lively attitude. Nonetheless she can be very serious and prudent when things are getting serious. Minako is quite popular among the other airbenders and is more or less the leader of the airbender students. However, she is often bored of the things they get taught, that's why some of the monks have problems to get along with her. But at any rate, they can't deny that she has a good connection to the spirit world.

~~~~~~~~~~

The following characters are not necessary for the role-play. However, if someone still wants to play them, then they should feel free to do so.

Haruka: Haruka is an airbender that lives in the Northern Air Temple. She stands out because of her personality which is livelier than those of the other airbenders. Nonetheless she gets along with almost everyone at the Temple. Many people are impressed by her when Haruka runs - she runs faster than anyone else and is even said to be as fast as the wind itself.
Haruka is in love with the princess of the Northern Water Tribe, Michiru, even though she never met her. The things she knows about Michiru are things she heard of others.
Side information: Haruka has a flying bison.

Michiru: Michiru is the princess of the Northern Water Tribe and doesn't have much contact to the world outside since she has to fulfill her duties as a princess. Nonetheless Michiru is a good waterbender who knows how to defend herself. However, because of her guards and the good safety in the palace she doesn't use her talent that often and is only waterbending during the training.

Hotaru: Hotaru is a non-bender that often flees from her home. She dislikes her step mother Kaori very much and can't stand it that she takes the place of her mother who died a few years ago. That's the reason why she flees and needs some time for herself to calm down. One day - after she ran away again - she ran into a graceful woman named Setsuna. Immediately she gets a feeling of safety and familiarity around her. It doesn't take long until they start to get along very well and soon they meet nearly every day and spend some time together. Later she learns how to block someone's chi.

Setsuna: Setsuna is a sophisticated woman that learned very early the art of chi-blocking. Since she is a non-bender, she had to find a way to defend herself in case she should get attacked someday. One day - when she was on the street to buy some things - a young girl ran into her. Setsuna introduced herself to the girl and soon they befriended. Since she loves kids, Setsuna starts to meet Hotaru regularly and later teaches her how to block someone's chi. She has motherly feelings towards Hotaru.

Except Rei/Makoto and Hotaru/Setsuna, the others don't know each other at the beginning.
The characters are as old as they were during Sailor Moon S.

As I said I'm still a beginner, so don't expect a masterpiece xDDD

Rei Hino:

Makoto Kino:

Minako Aino:

Usagi Tsukino: