Where can I edit the permalink /project-view/projectname in something like this /portfolio/projectname.
You can change the custom post slugs for Projects, Galleries, Staff, Downloads, Testimonials and Partners posts.
Go to WP Admin > Live Composer > Settings > Post Types and change values in the next fields:
Make sure to visit permalinks section after making these changes!
After making changes to the custom post type slugs, you'll have to visit WP Admin > Settings > Permalinks page. No need to change anything, just open this page in your browser. This way WordPress will know that URL in the database should be updated.