Shimeah is essentially the same word as Shimeam (1 Chronicles 9:38). The latter is a mimmated form (i.e., a more ancient form of the noun, with the original ending m).
And these also dwelt with their brethren in Jerusalem, over against them. — Literally, And they also, before their brethren, dwelt in Jerusalem with their brethren. The verse seems to tell us that of all the stock of Gibeon only the branch of Mikloth-Shimeah settled in Jerusalem. When, we are not informed. Some think the reference is to the repeopling of Jerusalem after the Restoration (Nehemiah 11:1). “Before their brethren.” — Before in Heb. means east, as behind means west. The clans in question dwelt in Jerusalem, to the east of their fellow-tribesmen in Gibeon.
With their brethren — that is, with the other Benjamite clans settled in Jerusalem (1 Chronicles 8:16-28).