*LandscapeOrientation: Plus90
/etc/cups/printers.conf
в секции для вашего принтера указать опцию orientation-requested
:<DefaultPrinter YourPrinterName>
..
Option orientation-requested 4
..
</DefaultPrinter>
orientation-requested=3 - portrait orientation (no rotation)
orientation-requested=4 - landscape orientation (90 degrees)
orientation-requested=5 - reverse landscape or seascape orientation (270 degrees)
orientation-requested=6 - reverse portrait or upside-down orientation (180 degrees)
sudo systemctl restart cups.service