Unlike the changelings of the west, the Hotei is a human on the brink of death, or just recently dead, in which the shinma supplants itself. This is not like the Changeling Way. When the hotei is destroyed the Hsien must find a new body for itself or be destroyed.
The Hsien are incapable of reproducing in their hotei form because they are once-dead bodies animated by the shinma soul. Some think there area limited number of hsien spirits and they must all live 1000 lifetimes before returning to the Celestial Courts.
In all, the Hotei is a convenient shell for interacting with mortals. The Hotei also makes using Wu Tan more difficult. Specific kwannon-jin powers are, likewise, inaccessible in the hotei form though Lucks and Curses work normally. Shifting to Hotei form from Wani Form costs one Yugen, as does shifting to animal form for the Hirayanu.
It is hard for other Shen to pick out a Shinma in hotei form, even if they know what to look for. Anyone other than another Hsien is at +2 difficulty to all perception or detection rolls to do so.