I expect these values should be hidden/visible even on the change of department correct??

If so,you would need an OnChange Client script. Try below:

Replace table, Field name to department

function onChange(control, oldValue, newValue, isLoading, isTemplate) {
if (isLoading|| newValue == '') {
return;
}
var dept = g_form.getValue('department');
if(dept == 'accounting'){
//show accounting apps
g_form.setDisplay('pep',true);
g_form.setDisplay('fas',true);
//hide non-accounting apps
g_form.setDisplay('salesforce',false);
g_form.setDisplay('factset',false);
g_form.setDisplay('dst',false);
}
}