User blog comment:IamJakuhoRaikoben/Chapter 492: Elder Sister and Younger Sister, Review./@comment-1359322-20160704160505/@comment-7418318-20160704163500

That she sent a thought projection still wouldn't mean that Mira is save.

We've never seen "Siegrain" perform any magic, but we saw him touch Erza. And I doubt that physical form alone was enough to cause Jellal such a big loss of power while the Siegrain thought projection was active, so I think that Jellal was able to cast magic (to at least some degree) through the TP.

If Jellal could (theoretically) do it, I'm sure Irene can (theoretically) do it too.