Do you have pictures of the whole plant showing the leaves, leaf arrangement on the stem, and any other distinguishing characteristics like flowers/flower heads? That is what is needed for identification.

It is, by the way, not mugwort. The leaf is wrong to be Artemisia vulgaris. The artemisia clan is large though and another member of the clan is possible but it is not possible to say without more info.

FataMorgana

Maybe a Perovskia aka Russian Sage?

It looks a bit like Perovskia to me too, but as the flowers are out of focus it's hard to tell. Could you post a clear picture of a flower?