Does tristana even have a proper powerspike anymore?

They moved her kit into early/mid game with the preseason reworks.

Her kit is AD scaling reliant with the damage on her E.

You can't finish IE first in it's current state. It's an investment item that requires one of the zeal items to be finished first to make good use of it which means no early game AD to scale with her E.

So does she ever have a time where her kit and her item power spikes line up an allow her to accomplish anything?

If so approximately what stage of the game is it?

I feel like by all rights she should be doing well in this meta with as much survivability and mobility as she has. But, she's the lowest win rate.