Conversion of xml files to vcard file format

You can certainly find utilities and other software tools that can be used to convert contacts from XML and parse them to CSV format, which is what basically represents xml to csv conversion. Once you have a .csv file with your contacts, you can use some of usual csv to vcf converters to get your vCard file. This will of course only work with XML files that contain valid contact sources.

Open XML file    Open VCARD file