I assume you are talking about increasing the rust resistance of non-stainless steel blades.
"Can." It will repel water just like grease, so it will help. Certainly I wouldn't expect it to hurt the blade. There are better things to use for rust-proofing, so maybe not "should".
According to Wiki, a lot of compounds labeled "neatsfoot oil" have mineral oils mixed in, so I'd not want to use a blade treated with such for food prep, if that's an issue to you.