No.

Operators who are already using ZUGFeRD can submit e-invoices to the federal administration using the 2.1.1 XRECHNUNG profile. They do not have to use the XRechnung standard in addition to that.  

When using ZUGfeRD in the XRECHNUNG profile, please note that invoices are accepted only as a structured XML file with no visual format.  

The ZUGFeRD 2.1.1 XRECHNUNG profile meets all requirements and allows invoices to be submitted via the federal invoice submission portals.  

Invoice issuers can thus use the XRechnung standard or the ZUGFeRD invoice format to submit e-invoices in accordance with the federal E-Invoicing Ordinance.