My goal is to output image that has been Image Trace in outline without clicking the Expand button and set the fill to none.

The problem are:

  1. Exporting the layer with View box set to Outlines will only export blank image.
  2. I need to compare 3 artboards (4/8/12 colour) and the outlines are different between the artboard. So, the solution down below will heat up my laptop.

The solution that I know:

  1. Click the Expand button, set the fill to none, and set the stroke color and width
  • Unfortunately, this is merely a duplicate of the question you linked to. Illustrator offers not ability to do anything with Outline Mode in terms of printing, saving, or exporting it. In some cases taking a screenshot of the outline mode may be sufficient.
    – Scott
    Commented Feb 20, 2022 at 6:38
  • You can't access the stroke and fill without expanding the trace. It's not possible. Instead, save your the trace first. Then do the Expand, change the fill and stroke colour, export as required, then close the AI document without saving. When you open the saved document, you'll be back to the original Trace before you expanded it.
    – Billy Kerr
    Commented Feb 20, 2022 at 15:12