Instead of WD-40, I like Camellia oil, but I don't buy it by the gallon -- in other words, it's just for precision tools and blades. It's ideal for any edge tool, knife, blade, chisel etc. I use it on plane blades, chisels, a marking knife and my straight shaving razor. I don't have any fine swords or knives but it is ideal for those. I also wipe the unfinished parts of Starrett tools with it.
For things like the lawn mower blade, hedge shears, shovels, and saw blades for green wood I use WD-40 or something like it - 4 in 1, Tri-Flow, Liquid Wrench etc. I realize these have a wide range of lubricity, but they all seem to work well enough for general purposes. WD-40 is a bit abrasive. Tri-Flow is really slick but more expensive (no reason to use it on a shovel). For machine tools I would look at something like Boesheild, but I don't have a machine shop.