https://userapps.support.sap.com/sap/support/knowledge/en/2998470
2998470 - 'Resend' function is missing in S4HANA 1809 and above system version when using new...
In S4HANA 1809 version and above, the function 'Resend' is missing and instead button 'Duplicated' is added when using new output management.