I have a stacked bar graph to include in my paper, which is going to be printed by reviewers in black and white only. When I print it out, I cannot tell the difference between some parts of it, which would otherwise be clearly distinguishable in color. Is there any way to make it readable even in black and white? Thanks in advance.

Have a look at the function presented in this File Exchange Pick of the Week to create hatched patterns instead of (or in addition to) your colors.
Here’s one example:
Here’s one example of how to use
applyhatch_pluscolor: