From the front you cannot tell. But obviously from the back, you can because the “pouch” is on the inside. Turned inside out, the little tag that secured the loose pouch is on the back but again, not noticeable. My SA suggested I hang a charm off it instead.
As far as the material goes, no there is no difference! The metal “ring” that closes the bag is not as shiny as the correct way round (it’s shinier metal the correct way round but it’s not noticeable).
From what I know, the way they make Kelly/Herbags, all Retourne and Sellier styles are made the exact same way, just Retourne’s are Sellier that have been turned inside out. So given the Herbag is canvas, there should be no difference either way in or out
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