Wep has a cheerful and naive personality due to her young age and lack of experience, with a tendency to be optimistic even about things that seem bleak. 

 But in this role, she has a concern to inform the Masterchief of a threat on a solar system scale.

I would like you to send a test voice acting as the character.

an example of the tone for the scene situation at minute 3:03 - 3:10.

Halo Infinite Ending - Cortana says Goodbye to Master Chief (2021)