The functionality to print an email in Outlook is similar to printing a Word document. If you need to print multiple emails for your record you can do so without opening each email and going through the process to print via the File menu. But this can be done only in the Outlook client and not in the Outlook app.
1) Select the emails you want to print.
2) Click File on the menu bar.
3) Select Print to open print options.
4) Click the Printer dropdown menu to open printer options.
5) Select a printer. In this example I have selected.
6) Click Print, to print all the selected emails at once.