According to Wikipedia, Guanyin can manifest in multiple forms.
"one of the most popular sacred texts in the Buddhist canon, describes thirty-three specific manifestations that Guanyin can assume to assist other beings seeking salvation. These forms encompass a Buddha, a pratyekabuddha, an arhat, King Brahma, Sakra (Indra), Isvara, Mahesvara (Shiva), a great heavenly general, Vaiśravaṇa, a Cakravartin, a minor king, an elder, a householder, a chief minister, a Brahmin, a bhikkhu, a bhikkhunī, a Upāsaka, a Upāsikā, a wife, a young boy, a young girl, a deva, a nāga, a yaksha, a gandharva, an asura, a garuḍa, a kinnara, a Mahoraga, a human, a non-human and Vajrapani."
So very like numerous other gods, goddesses and legendary/folkloric figures all over the world then.
By this reckoning, Zeus is a furry.
And using it to promote GI and "trans rights" (which already exist just like everyone else's) and preaching at you to be more Guanyin, is way overstepping what a public exhibit should do. Guanyin has nothing to do with today's transgenderism, but they think she does, so they are telling people to be trans.