Sorry, I don't know which one is her latest novel yet, so I can't recommend it.
I'm unable to recommend Claire Harman's latest novel because I don't have the information. But generally, when an established author like her releases a new book, it might be worth checking out. You can keep an eye on book blogs and reader communities. They are often quick to discuss and review new books, and once her latest novel is out, you'll be able to get a good sense of whether it's something you'd like to read from their discussions.
Since I'm not aware of Claire Harman's latest novel, I can't give a proper recommendation. But if you like her previous works, chances are her new one will also have some of the same elements that attracted you in the first place, such as her writing style, the way she develops characters or the themes she explores.