Not to sound pedantic, but
virtute looks like an
ablative of
virtus, virtutis (3rd
declension).
The ablative is a very strange
case for the
subject of a sentence. Very, very strange. One might even say that it is the
wrong case.
One would expect the subject to be in its nominative, which in this case is virtus, leading to the more traditional, and possibly less wrong formulation:
IN MEDIO STAT VIRTUS
In the spirit of aurea mediocritas and Epicurean moderation, may I suggest that Latin sentences be cited in a canonical form ?