It doesn't matter how you go about it, those crates will not look like scale plywood. Just because something is made out of "real plywood" is no guarantee that the final result will be convincing. There's nothing in nature that can simulate what real 1/160 plywood would look like.
I'm sure your mind is made up but after writing my last response I thought about how I would go about creating a plywood crate. I went on an online image search and found many pics of plywood, most were not the entire 4x8 sheet. After looking at about a hundred or so images I found a single image that had 10 4x8 sheets on it. I went to the page where it came from and it was a company that does 3D modeling. I did a screen capture of the low res image and brought it into Photoshop for a closer look. After resizing the image from 72dpi down to 300dpi the image ended up close to N-scale. I printed it out on a high-quality paper at 98 percent reduction and it was spot-on. I carefully colored all the white edges with a brown marker. Now I have a highly detailed set of 10 4x8 sheets of plywood for a future project.
For crates, I would make the basic boxes out of styrene and either make decals of the plywood sheets or glue the printed out plywood directly on the styrene boxes. Adding 1x bracing would finish them nicely.
