\defaultfontfeatures[MonaspaceXenon-SemiBold]
{
  Extension=.otf,
  UprightFont=MonaspaceXenon-SemiBold,
  ItalicFont=MonaspaceXenon-SemiBoldItalic,
  BoldFont=MonaspaceXenon-ExtraBold,
  BoldItalicFont=MonaspaceXenon-ExtraBoldItalic
}