No, not all blades can be sharpened using whetstones. Serrated blades, with their individual notches, require a specialized tool for sharpening. Attempting to use a whetstone to sharpen them can damage the blade. Instead, use a honing rod to sharpen in between the saw-toothed blades.
However, most other blades with beveled or straight edges, including cleavers and multi-purpose kitchen knives, can be sharpened effectively using whetstones.