Thank you chxcolatexmxlk for the suggestion of doing their ethnicities

Kai and Nya are Japanese

Lloyd and Seliel are European

Jay, Zane, and Pixal are American

Cole and Skylor are African-American

They all speak English

Kai and Nya know Japanese

Seliel knows Chinese and Spanish

Zane and Pixal can speak any language

Jay and Lloyd only know English, but Nya's trying to teach Lloyd Japanese.

Cole knows Latin (this is because Lou is a singer)

Skylor knows French, when Jay found out he begged her to teach him so he could impress Nya