Say both Sora and Rilku start at level 1

[adngo714 36]

Will they share their level gaining or will they both level up seperately?

[PillowHead 569]

"both Sora and Rilku start at level 1"  

I would assume that they level up separately.

 

[Arthur Twining Hadley 60]

Separately, specially if they're going to add Co-Op or a Battle Mode

[Caity 3,946]

Level up separately, like they did in KH3D.

[Crown Unlimit 234]

I agree with everyone else. Even if Riku will just be a party member (which I doubt) he will level up separately, like how Donald and Goofey did in 1 and 2.

[HarLea Quinn 26,501]

Level up separately most likely like in prior games

[Rob 5,571]

Are Sora and Riku in the same party?