When you cast it, Altered Ego is a Shapeshifter without Changeling--it only has one creature type. It doesn't become a copy of another creature until it resolves and enters the battlefield. Altered Ego would not get the Morophon, the Boundless discount unless you chose Shapeshifter with Morophon.
July 13, 2019 2:24 p.m.
The problem is that Morophon, the Boundless gives a discount to casting spells with the creature type. Altered Ego is only cast as a Shapeshifter. It enters the battlefield as a copy of the chosen creature, but by then it's too late to receive Morophon's discount.