It really depends on the type of editing and the editor. In general, proofing and copy editing is the same across fiction and creative non-fiction. However, the editor may not enjoy manuscripts outside of her interests. Developmental and Substantive editors, in my experience, tend to have strong preferences across types of creative non-fiction and fiction. Some even specialize in certain genres. I strongly believe that the editor you hire should both understand and enjoy your genre or type of novel. It’s a better working experience for both the writer and the editor.