On Windows Virtual Desktop's Privacy Page you can request and collect all the privacy and GDPR related information that Windows Virtual Desktop is providing.
The privacy policy by is a legal document or statement that discloses how Windows Virtual Desktop gathers, uses, discloses, and manges their customers' data.
The basis for Microsoft sharing, adding, uploading, hosting, accessing or sending personal data out of Europe. Vendors can also add a description of their own impact assessment for data transfers.