How to mass download invoices in PDF format.
SAP S/4HANA Cloud
In S/4HANA Cloud you can download multiple PDF from Billing Documents Using API_BILLING_DOCUMENT_SRV/GetPDF. The action itself is called for one Billing Document, however, with a Batch request you can have multiple GetPDF action calls in one OData Request (API).
You can also achieve it with a generic way by following this process: Mass Download of Billing Documents Output for Commercial Projects (5BP)
KBA , SD-BIL-GF-OC , Output Control Billing , How To