Earlier quoted context omitted.
There are hundreds of people with similar voices. If any voice actor can pull the same accent than Ms. Johansson, it should be fair game, as long it was the original training material? Voices cannot be copyrighted or be exclusive, although I am sure Hollywood will try to copyright them in some point.
In back to the future II, Crispin Glover didn’t sign up to be George McFly so they used facial prosthetics and impersonation to continue the George McFly character. He sued Universal, and reportedly settled for $760,000. Example article on the topic - https://www.hollywoodreporter.com/business/business-news/bac...
Setting a precedent that if your natural voice sounds similar to a more famous actor precludes you from work would be a terrible precedent to set.