This Raven differs greatly from her canon counterpart. Raven and her brother Qrow were former members of a tribe of raiders who lived far beyond the walls of Vale. Qrow was always the more streetsmart and smooth-talking of the two, while she only cared about the path of a warrior, immersing herself in tradition and ceremony for her tribe. This would create a very cold, aloof personality at Beacon, incredibly skilled in combat but completely tactless when speaking to others.

She would later abandon Vale and Team STRQ for unknown reasons, becoming a fugitive and a wanderer, travelling the world and taking whatever she deems worth taking.

For Raven's voice, I imagine her having a very noticeable, distinct accent, painting her clearly as someone far from Vale, as someone who is a proud warrior, or someone who has travelled along the coasts and has dealt with seediest underworlds and black markets across Remnant. This is true for both her young and adult selves.

Do explore and include multiple accents in your takes that you think may suit her description.

Her voice should be relatively deep and mature-sounding regardless of age. She has a somewhat unfeeling voice without a hint of humour or vulnerability, sounding aloof at times, as if very few things can faze her, but still not too monotone. Her voice is strong and commanding, but not loud or boisterous; rather it makes you feel threatened by her without her actually showing explicit hostility. This is a person who could kill you if she wanted to, she just doesn't have any reason to at the moment.

She would sound essentially identical as a teenager to her adult self, always sounding mature for her age.

EDIT: For those further auditioning for Raven, her accent would be Irish, Welsh or Icelandic, whichever you are proficient with.

Sketch of young Raven during Beacon, wearing her warrior's armour crafted from Grimm bones.

Adult Raven, atop her battleship.