Virtual DJ is offering a web interface where users can publish playlists they have made. Named "CloudLists", these lists can be found here: https://www.virtualdj.com/cloudlists/
If you want to export them to Spotify, Apple Music or any other music service supported with Soundiiz, simply copy the URL of the CloudList page, like: https://www.virtualdj.com/cloudlists/9111/index.html
Then, simply go to Soundiiz web application, select "Import Playlist" in top right and "By URL" and then, paste the URL and follow steps.
That's all, your playlist will be matched with the destination platform you have choosen!