There is no "outfilter" command line parameter - because it's not needed: export filter parameters are optionally passed to --export-to after a comma after output extension - see documentation.
Still - there is no such PDF export filter parameter, and thus you only can use a dedicated pre-configured user profile (create one and copy to some directory), using -env:UserInstallation=file:///path/to/profile/with/pdf/a/config.