On Square Point of Sale's Privacy Page you can request and collect all the privacy and GDPR related information that Square Point of Sale is providing.
The privacy policy by is a legal document or statement that discloses how Square Point of Sale gathers, uses, discloses, and manges their customers' data.
The basis for Block, Inc 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.