Mario Sports Mix character details

Shiroma (White Mage): Technique
Ninja: All Around, blink through enemies in basketball + slam dunk with a mirage shot
Kuroma (Black Mage): Tricky, fries players with lightning bolts in hockey
Moogle: Tricky
Cactuar: Tricky
Mii: All Around, can use a super spike special attack in volleyball

Source 1, Source 2