If you need to remove the cropmarks from the AutoPublish PDF, follow the steps below in Adobe Acrobat DC:
Link to notes on Adobe's website: https://helpx.adobe.com/uk/acrobat/using/crop-pdf-pages.html
Last updated on 12 Dec 2022 | Also Applies to Adobe Acrobat 2017, Adobe Acrobat 2020
You can adjust the visible page area using the Crop Pages tool and the Set Page Boxes dialog box. Cropping pages can help you create consistency within a PDF composed of pages of different sizes.
Crop a page using the Crop tool
Cropping does not reduce file size because information is merely hidden, not discarded.
Choose Tools > Edit PDF.
The Edit PDF toolset is displayed in the secondary toolbar.
In the secondary toolbar, select Crop Pages.
Drag a rectangle on the page that you want to crop. If necessary, drag the corner handles of the cropping rectangle until the page is the size you want.
Double-click inside the cropping rectangle.
To apply these settings to more pages, set the page range or select All under Page Range.
Note: In testing selecting All as the page range did not work for me. I would recommend using the From - To page range setting and add the last page number in the To field.
6. Select OK to crop the page or pages.
Optomize PDF File Size
If you need to reduce the file size follow the steps in the link below to Optimize the pdf in Acrobat Pro: https://helpx.adobe.com/acrobat/using/optimizing-pdfs-acrobat-pro.html
Follow the option Advanced Option to reduce the PDF file size.
I've just tested it and it reduced a 35MB file down to 9MB