I can't see WBs on that table.they are not the same as a FB. More likely to cover the ground of a Winger and a FB combined.
By the numbers is looks like they've been added to FB. I take your point (and you might be right) but it doesn't really matter when we don't play with WBs... in a 4231/433 wingers are most likely to be substituted meaning we could do with another quality winger as we only have 3 natural ones