They seem to have locked down the local storage approach to the following requirements: https://labelstud.io/guide/storage#Local-storage:~:text=Add%20these%20variables%20to%20your%20environment%20setup%3A

Alternatively, you could serve the images on a different port to ls (I don't see why changing ls port would do anything RE comments above) and paste the URL to the image in the task JSON. However, the challenge here is that it depends on your setup. For example if you're using a docker container for ls and another container for the image server, even when they're on the same network, ls can't see the images - this is the challenge I'm facing anyway.