Albania: Valbona to Theth Hike questions

Hi all

I am planning to do the Valbona to Theth hike on a solo trip in late June this year and I am looking for some advice.

I will be travelling around Europe for a few weeks before this and so I won't be backing my hiking boots as I don't want to carry them around with me for 5+ weeks just for 1 day of hiking. My question how have people found the hike wearing normal running shoes? Would they be okay to wear?

My second question is just on the general difficulty of the hike. I am not unfit but I would not call myself extremely athletic or anything. Do you need to be very fit for the hike or would a moderate amount of fitness me suitable for it?