Unfortunately there are a number of command line options that can only be set via command line options and are not able to be to set inside a .gbc file. A task did exist in the past to look at that but was unfortunately not implemented, see.
https://4js.com/support/issue/?id=GDC-2725. There are some valid reasons for not implementing, for instance it would not be desirable to allow -A 0 , --listen ANY. On the other hand there are some such as the -X you are after, -p 6401, --language, -c , command line arguments where it would be nice to specify inside the .gdc. You also face the problem of what if two shortcuts have two conflicting argument, for instance if one specified -X and one did not ...
For now, you face the same problem as someone who wants to launch any other application Excel, Word, Chrome etc with specific command line arguments for Excel, Word, Chrome etc. It is possible but you either have to get into the shortcut/registry settings so that gdc.exe -X is launched instead of gdc.exe, or you associate a .gdc file with a .bat file that in turn launches gdc.exe -X -%1 etc i.e it becomes a Windows Shortcut problem
