While Trados Studio supports XLF/XLIFF files of version 2.0 through the XLIFF 2.0 File Type, these files are currently not supported in WorldServer. Only XLF/XLIFF files of version 1.2 are supported by the XLIFF 1.2 File Type.

Note: XLIFF 2.0 has a different DOM structure compared to XLIFF 1.2. As a result, the two formats are incompatible. Simply changing the version number at the top of the XLIFF file to 1.2 (or vice versa) will not work as a solution.

The RWS Professional Services Team might be able to create a custom file type configuration. Please note that this service is chargeable. Please refer to this article to request the assistance of the RWS Professional Services Team:

How do I request assistance to upgrade, configure, or refresh my WorldServer or TMS environment or to create a customization?