Design and write characters for all the major countries in WW2 as female high school anime girl, they all attend the same school.
For example (rewrite this example too)
American-chan: 
Looks: Tall and athletic but is on the chubbier side. She has slight tan, blue eyes and has short messy blonde hair. She wears sun glasses and American flag shorts. 
Personality: She is loud, proud and is full of energy. She love money, buys all the latest stuff and is super rich. If you mess with her stuff, she not afraid to fight and might even bring a gun to school. She's a natural leader and is part of the student council. Though she very laid back and won't take action until it effects her. Her favorite food is the burger. She constantly mispronounces everyone's name.
Sure, here are some examples of what each character could be like:

Japanese-chan:
Looks: She's on the shorter side, with long straight black hair and a neat school uniform. She always carries a fan with her, which she occasionally uses to hide her face when she's feeling shy or embarrassed.
Personality: Japanese-chan is very polite and respectful to everyone, but she can also be fiercely competitive. She's part of the school's kendo team and practices every day to improve her skills. She's also a bit of a traditionalist and enjoys tea ceremonies and flower arrangement. Her favorite food is sushi, and she's always trying to convince her classmates to try new Japanese snacks.

German-chan:
Looks: She has short, sleek blonde hair and bright blue eyes. She wears a military-style uniform with a red armband and often carries a small Nazi flag with her. Despite her intimidating appearance, she's actually quite small and delicate.
Personality: German-chan is very strict and disciplined, always following rules to the letter. She's also incredibly smart and excels in all her classes. However, she can be a bit cold and distant to her classmates. She has a strong sense of national pride and is always talking about the superiority of the German race. Her favorite food is sauerkraut, and she's always trying to get her classmates to try German cuisine.

British-chan:
Looks: She has long curly brown hair and wears a school uniform with a plaid skirt. She also wears a bow in her hair and carries a small umbrella with her wherever she goes.
Personality: British-chan is very polite and well-mannered, always using proper etiquette and speaking in a posh accent. She's also incredibly smart and loves reading books. She's part of the school's debate team and always argues for the British side. However, she can be a bit snobbish and dismissive of other cultures. Her favorite food is fish and chips, and she's always trying to convince her classmates that it's the best dish in the world.

Soviet-chan:
Looks: She has short curly red hair and wears a red scarf around her neck. She often wears a military-style uniform and carries a hammer and sickle emblem with her.
Personality: Soviet-chan is very tough and no-nonsense, always standing up for what she believes in. She's part of the school's wrestling team and often uses her physical strength to intimidate others. However, she's also very loyal to her friends and will do anything to protect them. She has a strong sense of class equality and is always talking about the benefits of communism. Her favorite food is borscht, and she's always trying to get her classmates to try Russian cuisine.

Italian-chan:
Looks: She has long curly black hair and wears a school uniform with a red necktie. She often carries a small accordion with her and wears a beret on her head.
Personality: Italian-chan is very outgoing and loves to socialize. She's part of the school's drama club and often acts in plays. She's also very passionate about music and often sings or plays the accordion for her classmates. However, she can be a bit unreliable and disorganized at times. She has a strong sense of family and is always talking about her large Italian family. Her favorite food is pizza, and she's always trying to get her classmates to try authentic Italian cuisine.