SoPDF does not rotate the page if you choose the -m2 or -m3 options.
If that's not good enough with your needs, I'd probably do this with a combination of ghostscript and calibre's pdfmanipulate command line program. I posted instructions for doing this on linux in
another active thread here. But perhaps it would be worth investigating how to do it for Windows. If I get some free time, I'll try it out. It should be more or less the same process.
There's a PERL script called PDFCrop--part of the LaTeX bundle--that also works well, though I'm not sure that's been tested on Windows either.