>>719014015
Im inclined to say roxas became his own identity due to being a mix of both sora and ventus so he is either but also neither of them, he's a schrodinger's identity which is why it justifies why he can dual wield as ventus had a history of meddling with the darkness while sora was the LIGHT that healed ventus. I believe that Roxas thought he could merge with Sora but turns out that Roxas cannot be trully merge with Sora because he already forged an identity of his own.
Namine is an entire concept which would easily disregard as a special rule for being a princess of light BUT I can ramble about how ventus' heart influenced kairi's heart forming namine in return since ventus carried the darkness that were plotting to mess around with MoM perhaps some of that ability was transferred to namine making her able to predict what would happen.