I do know that the image is going to have to be eventually converted to CMYK, naturally, but I was wondering if there was any way to avoid having to do this manually, maybe by applying some setting during the export.
I have tried converting the image to CMYK Fogra 29 inside the photo persona, used it inside the Publisher file and then exported it as a PDF for print. The result is clearly closer to what I wanted to achieve, but there are still obvious differences (see the second and third image below).
Also, when I converted the image to CMYK, although it exports to PDF correct-ish, it displays weird inside Publisher, which makes judging if the image is correctly colored or not a hassle. Is there any way to force Publisher to display the CMYK image as Acrobat does with the exported PDF?