It isn't an issue. It was debunked. The machines are calibrated for sharpie and pens. Source: I voted in Scottsdale with a sharpie.

"Despite a flood of social media posts on the rejection of Sharpie-completed ballots, Maricopa County officials said Wednesday on Twitter that the markers are "not a problem for our tabulation equipment, and the offset columns on ballots ensure that bleed-through won’t impact your vote."