Create a PDF file with the crop mark as you want it. Then use the watermark preset to place this 8 times around the PDF's trimbox.
Make sure to select the option to place the marks "outside" of the selected PDF box and then define an offset to push the marks away from the corner. You should be able to use a single PDF for all 8 marks.
Once you define that watermarks preset you can use it in all your workflows. It will be shared between workflows so any update to the preset will be reflected in all workflows that use that preset.