thank you. I would assume that Zotero does not use any cryptographic algorithms or non-standard encryption. But even if it does, since the license is publicly available, it is not subject to any export control regulation. hope this understanding is correct.
Published open source software is generally not subject to the EAR.
https://www.linuxfoundation.org/resources/publications/understanding-us-export-controls-with-open-source-projects