Eduardo was recently acquired by E-sports team CYgames, and with his career in Street Fighter 4 and his recent quality of play in SFV, it's easy to see why. His Necalli was strong, and with Balrog having improved since Season 1, he looks forward to showing everyone why he is worth the Fight Money.
Karin's laugh and mannerisms are derived from the unpleasant "ojou" stereotypes common in anime and manga as well as the "rich person"/"popular schoolgirl"/"spoiled brat" stereotypes of Western fiction; while she typically remains snobbish and haughty as per the standard, other aspects of her personality can vary wildly in other media. In Namco x Capcom, Karin is calmer, more level-headed and cynical, and serves as the voice of reason for the impulsive Sakura (though she still retains her trademark laugh and condescending comments during battle sequences).
Balrog is generally self-centered, hot-tempered, arrogant and sadistic. He is a belligerent pugilist who possesses an insatiable urge for money and a vicious, bullying mean streak, often refusing to take responsibility for his actions. Despite being a once great prize boxer, Balrog has intentionally cheated in his fights whenever he felt like it, and has even killed one of his opponents (though by accident).
Chun-Li is a resourceful and dedicated officer of the law with a strong sense of justice that rivals that of her father, as she strongly believes in protecting the innocent and saving the lives of others.