A little late 😉 , but I've recently been experimenting with post-processing sketchup output for a screentoned comic strip effect, and it's definitely possible to convert sketchup shading into hatched shading in photoshop or GIMP. If you separately export

hidden line shading with edges of your choice
and monochrome shading with no edges

Put the hidden line shading on a layer in your image editor of choice, then put a hatched texture on a layer above it. Now use the monochrome shading (inverted) as a mask for the hatched texture. Play with the levels on the mask to change how dark an area has to be to get shading.

Et Voila!

Quick and dirty, but I did a sphere with two layers of hatching, one for only the darker areas by levelling its mask accordingly

https://i.imgur.com/BovM2lC.jpg

And here's a spaceship that I used this method to screentone (starting with a few more outputs - sun shading, flat colour, etc):

https://i.imgur.com/z7FkZtH.jpg