If your installation of Dataverse doesn't have the Croissant exporter enabled, you can create a Croissant file client-side using pyDataverse.
Please note that pyDataverse creates a Croissant file that is somewhat different than the one generated server-side by Dataverse. Hopefully it will be close enough for your needs.
Also note that the dataset must be published for this script to work.
python3 -m venv venv
source venv/bin/activate
pip install -r requirements.txt
python create-croissant-client-side.py