Apparently Lillie is UB-01, due to an uncanny resemblance.
“UB-01’s body is composed of a glass-like substance. However, it’s constantly changing shapes, never settling on one.
While evidence of something like a survival instinct can be observed in UB-01, no one knows whether it has a will of its own or any emotions. It’s said that, for some reason, its movements resemble those of a young girl.”
Though Pokémon has allowed shape-shifting abilities before, I’d like to think they’re not one and the same. The “same age as your character,””working as Kukui’s assistant for personal reasons,” “but she loves reading and has devoured many books,” makes her sound very un-Pokémon like. If she is related to Lusamine and Gladion, then my guess is the Aether Foundation isn’t studying Ultra Beasts, but creating them. It makes sense considering the code name UB-01, like an experiment (alchemical?) And the similarity between Lillie and UB-01 might simply be because it was based of her, or she was the basis of its existence, then the next Ultra Beasts will bear similarities to Gladion and Yusamine. A bit farfetch’d but maybe it’s just me not wanting her to be a Pokémon.