Change sender and print format language when using auto repeat

We’d like to use auto repeat in order to create recurring invoices.

How is it possible to change the sender of the auto created E-Mail?
E-Mail is send by Administrator, but should use the sales account.

How can the print format language be changed?
We use one print format in different languages - when sending a mail manually, I can select the print format and the language, in auto repeat you only can select the print format.

Thanks in advance!