Features
The target’s features from classes, themes, and so on still work in its new form. However, its form could limit the usage of features it has. Rely on common sense and GM guidance in such situations. Additionally, the target can’t gain class features, theme features, class grafts, and similar mechanical elements from a polymorph form. For instance, you can’t polymorph a target into an Aeon Guard to grant a target the benefits of that creature’s class graft, but you can transform a target to look like an Azlanti human.
Source
Alien Archive 2 pg. 144