You seem to be one of the few to echo my experiences that boots and shoes fit may need to be sized differently.
A Barrie PCT boot fits me best in 8E, but the Barrie LWB can fit me in 8D or 7.5E.
I think the construction/style of shoe matters; the last is the general shape, but the vamp feel with respect to your instep can be different. Consider shoes that are whole cuts or that have stitching seams on the tongue. An SA once told me this can put pressure on the top of the foot.