Hello,
-shellPrint always prints directly without a dialog. For a print dialog, use the PDF24 Reader instead of the DocTool in your command (pdf24-Reader.exe is in the PDF24 installation folder):
pdf24-Reader.exe /printDialog /printTo "NAME" "${file}"
/printDialog opens only the print dialog of the PDF24 Reader with a preview, without the Reader window. /printTo preselects the printer, which can still be changed in the dialog. The file is printed when the user clicks "Print"; on cancel nothing is printed. The switch is available since version 11.31.0.
In this dialog you can choose the printer, paper size, duplex, grayscale, copies and the pages. Settings that only the printer driver offers, such as the output tray, are not in it. With the next version, the PDF24 Settings get the option "Always print using the system dialog instead of the PDF24 print dialog" under Reader. With this option, the same command opens the Windows print dialog of the printer directly, with all driver settings, as you described.