Though this Interactive story is promising, there is another that has transformations about Samus. It's called 'Metroid: Hall of Upgrades' and it's on the Writing.com website. It's about Samus Aran picking an upgrade from a wide assortment and changing into that upgrade. So far, it's really promising from her turning into animals, inanimate objects, regressing in age, and turning into different versions (teacher, nun, angel, etc.) If you want to see it for yourself and begin writing, here's the link:
Metroid: Hall of Upgrades