Try increasing width and height in crop settings for more space for croping marks (i.e. try H=11.8in, W=8.9in). Note that it is not A4 paper but smaller. However, after cropping you get page in B5. The logic is, you use geometry package for setting (logical) page dimensions, how it will look at the end, after cropping/trimming, and you use crop package for defining dimensions of the paper on which document will be printed (so, dimensions set by crop must be larger than those set by geometry).