I created a white text string with a dark shadow in the LR watermark editor. When printing to a jpg file, the shadow did not appear although the text appeared correctly (flat - no depth). I then tried to print to a printer, selecting a PDF printer in the printer dialog box (MacOS 10.14), the shadow appeared correctly in the pdf file. I tried various combinations of printing options, and decided there is a bug in printing watermarks with shadowed text to a jpg file (print to file). I printed the image to a pdf file, imported to photoshop, the saved as a jpg file to get around the problem.
Latest version of LIghtroom Classic (2020) as of 2020/02/11.