How did Elain do it?

As I’m sure everyone is familiar with, in ACOWAR Elain stepped out of a shadow to kill Hybern despite having been placed across the battlefield. It’s seems extraordinarily likely she somehow shadow traveled especially since the other instance we see this wording involves Azriel stepping out of a shadow in the same book.
The question is how? Is she a shadowsinger? Can she borrow powers? Did Truthteller allow it? I know some people theorize TOG spoilers Elain and Azriel are carranam which is possible, but in TOG when carranam borrow power, they’re really borrowing strength/energy. The output is still their own power. They also need to actively have a blood connection. But they’re different worlds so things could be different. Do you have a different theory on how she shadow traveled or do you believe it wasn’t shadow travel at all. What do you think?

Unless it is directly related to your theory, I encourage everyone to leave shipping out of this post and focus on powers because no matter who Elain ends up with there has to be an explanation.