I walk from Broad St NJT to Norfolk St via Orange all the time at night. Sometimes even Penn to Norfolk, but usually via Central Ave.

Full transparency, I'm white and have lived in Newark for five years. I stick out like a full moon around here. Other user is correct; basically guaranteed safety during the day. At night, you'll be fine. Just walk like you mean it. No one is usually around, and if they are, they'll be walking like lightning as well.