I dont use erasers on wood, I'm afraid of contamination. Would rater sand or plane off the markings. , I, know if I sand there is still a possibility of graphite contamination, but less than graphite and eraser combined.
Also, if you erase, I would think that you are pushing the eraser and graphite deeper into the wood.
In the overall scheme of things, I don't think it matters, I'm just freaky about the surface prior to spraying.
I just about use lacquer exclusively and so contamination is a biggie.
Tony B Retired woodworker, among other things.
"Strive for excellence and settle for completion" Tony B