[quote=@Dynamo Frokane]


Xianghua Seong Mi-Na and Cassandra  dont vary much in terms of being young spunky adventurer girl looking to support thier significant person (Kilik, Yun-Seong & Sophitia respectively).[/quote]


Seong Mi-Na is a tomboy who wanted to prove herself and, when denied entry into military service because of her gender, set out on a foolish quest to claim Soul Edge which was pre-emptively ended. She ran away again because she didn't want to be married off and wound up losing to Ivy because she was cocky and over-confident. She's not looking to support Yun-Seong. Yun-Seong got denied training by Mi-Na's father and she felt sorry for him, gave him an heirloom, then decided to chase after him to keep him from getting Soul Edge because it's an evil sword. 

Xianghua is spunky and childish and got wrapped up in the Soul Edge business because she was a member of the Imperial Guard and the Emperor of China wanted the sword - she met Kilik and Maxi and joined up with them partly because the sword is evil and partly because of her mother. Good thing, too, since Xianghua's sword turned out to be Soul Calibur. After falling out of favor with the Emperor for failing to find Soul Edge and learning that there are Soul Edge fragments, she decides it is her duty to destroy them. Kilik doesn't enter the picture until later when, yes, Xianghua admits that she has feelings for him, but her goal was always to destroy Soul Edge not support Kilik. She leaves Kilik behind to train harder only to reunite by chance later on. 

Cassandra is hardly spunky adventurer girl considering her quest is to shoulder her sister's burden and in the process have a crisis of faith before determining that the one she has to believe in above all is herself. She's the opposite of her sister in that she's more brazen and aggressive (Which is reflected in her gameplay style). 

I don't think it's fair to say they have the same personality apart from them all being women who get swept up in the Soul Edge nonsense for wildly different reasons.