1. Convert the PDF to an image format, for example by using the website:
https://pdf2jpg.net/convert.php#.XsPp-2hKjIU.
2. Colorise the image so that all black ink is changed to blue. I personally have used this website:
https://manytools.org/image/colorize-filter/. I select the "Screen" option.
That's all it should take. Your printer should now be able to print the document.