Changeling: Does "Polymorph" mean Fly Speed/Swim Speed?

[Rossebay]

Alright, so Changelings can be found in this Unearthed Arcana article (https://media.wizards.com/2018/dnd/downloads/723UA_EberronRaces7232018.pdf). What I'm wondering is, based on their ability calling it Polymorph, if the Changeling player were to change shape into a, say, Winged Tiefling or Avariel, or some sort of Merfolk (from the Placescape books), do they gain the extra movement modes that those races possess?

Obviously it can be decided by Rule Zero, but I'm looking for RAW here.

[Eragon123]

Usually Polymorph changes stats.
Changelings' shapechange does not.
Movement speeds are a stat.
Ergo no.

[JeffreyGator]

Changeling is almost a direct cut/paste of one option of alter self.

Aquatic adaption and natural weapons are different options not included.

Wings would be a change in form from bipedal and is also not allowed under alter self in 5e (it was in 3.x and 2e, I think)