A friend of mine, with a doctorate in Linguistics, was reading the
Harry Potter books to her young sons and told us about it at Book Club (which I soon dropped out of ...); they loved it, quite predictably, but it soon became clear that she (a) couldn't pronounce
Hermione, (b) didn't know that she couldn't and (c) in the interests of accuracy had to be put right. So I did, and she was amazed but grateful! Her best guess had been HERmoyn.
So, not so sure that folks will know how to say it, unless they've seen the movies or played the audiobooks. But it is lovely and distinctive, as you say, and they can learn.