Can an easement be sold or transferred separately from the property it was created to benefit?

Generally, no, if it's an easement appurtenant. This type of easement is tied specifically to the dominant land itself, not to whoever happens to own that land at any given moment, so it can't be sold off or transferred as a separate, standalone asset apart from the property it benefits. It simply moves automatically with the dominant land whenever that property is sold; there's no mechanism to sell just the easement while keeping the rest of the property, or vice versa.

An easement in gross works differently, since it benefits a specific person or entity rather than a piece of neighbouring land, think of a utility company's easement for its pipeline or power lines. Depending on how it was originally created and worded, an easement in gross may be assignable to someone else independently, though this isn't automatic either and depends entirely on its specific terms.

For most everyday situations between neighbouring homeowners, a right-of-way or shared driveway easement, for example, the relevant type is almost always appurtenant, meaning the practical answer is that it simply can't be separated from the land it benefits and sold on its own.