The only potential sba to xml conversion we know about, is export of accounting data from the old Dutch software called SpeedBalance, to XML format. This is was certainly option in the original version of the software, but since it was acquired by Banana SA.
It appears that SpeedBalance is now part of Banana accounting software or was just acquired by the company, but there are no mentions about any how to convert sba to xml on their website, of if the files are even usable anymore. Thus, your only remaining option might be to reach out to their support for further assistance.