I don't exactly follow you.
SFML doesn't have any format which would read vertex arrays, so you would have to define one of your own, which then clearly won't have any editor since you just invented that format.
Also I'm not sure what you are trying to achive.
For clearification a vertex is just a point, normally in a three dimensional space, but in SFML, since it's 2D specific, a vertex has only two coordinations. A vertex array is just a collection of vertices.
So every tool that can create animations of points could be used to generate some format, which then again with some work could be loaded by your own function into your SFML project.