Mobled Queen

The word "mobled" is from "moble" which is a Middle English word referring to personal property, as opposed to real estate. A "moble" is a movable good, i.e. an item of property which can be moved. The past tense makes it a "moved good."
Shakespeare had a bit of fun there. It is extremely obscure wordplay. When he had Polonius say, "that's good," Shakespeare was providing a clue to what "mobled" means. There is, indeed, a kind of reference to "good" in the word.
The Polonius character, himself, has no idea what the word means, he only noticed it sounded interesting, and heard Hamlet remark upon it, and he's trying to be congenial after Hamlet chastised him. By pure coincidence - Wheel of Fortune Motif - Polonius happens to say part of what "mobled" means, but he doesn't know it.
For plain reading, the phrase mobled Queen simply describes Hecuba as a "moved good Queen."
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