[Outlook]How to print in background and change 'Paper Size' dynamically?

I am developing a printer which based on Office Outlook, but are stuck on the two flowing issues:

• Can’t find ‘Print in background’ option in Outlook, this option can be found in Word

Are there some interface functions so that we can change this configuration dynamically?

• How to change ‘Paper Size’ dynamically in Outlook when print?

I can’t find ‘Paper Size’ related interface functions in Outlook, and can’t find related document. If possible, please prme code snippet to use these interfaces.

I can find related settings in UI, but not interface functions.

I hope I can get your help, thanks!