Send E-Mails "on Behalf of" from WebCube

When configuring an SMTP-Server for sending mails via webCube it is only possible to check / uncheck "Use as sender Adresse":

https://services.sergroup.com/documentation/#/view/PD_webCube/14.1.1/en-us/AG_Doxis_webCube/WEBHELP/APP_webCube/topics/ref_adm_SMTPsettings.html

We would like to have the option to configure "Send on Behalf of", so technically the technical user is used for sending the mails, but on Behalf of the logged on user, instead of "Send As" the logged on user.