Sounds like White Dwarf. It was a failed pilot for a series, I think.
Wikipedia summary:
In the year 3040, New York medical student Driscoll Rampart (Neal McDonough) is completing his internship on Rusta, a rural planet which due to it being tidally locked to its primary, is divided into contrasting halves of day and night with the halves separated by a wall. The two sides are involved in a civil war: The day side containing a Victorian-styled colony is at odds with the night containing a medieval kingdom. The differences between the two cultures leaves Rampart in a state of wonder. Rampart arrives from Earth for a six-month stint at the Light Side clinic run by Dr. Akada (Paul Winfield). Rampart's ambition is to eventually set up a private practice in Manhattan on Park Avenue.
Some related questions:
Show about half of the world on perpetual night and the other on day. Which has a link to the full movie.
Fantasy TV series from the 90s
90s fantasy movie about a magic world split light and dark Which has a link to a MUCH better synopsis (emphases mine):
Driscoll seeks refuge outside, but the wind is up. A child patient nicknamed Never meets him. Never is an empathic shape-shifter whose powers are known to the Rustians as Proteus Syndrome. He is a societal pariah to his wealthy parents as he morphs uncontrollably into anything from a boy-sized raven to a panther. He can even change into the loved ones he finds in the minds of the people nearest in proximity to him -- including Driscoll's recently deceased fiancé.
Elsewhere in this fantastical world dwells a fantastic, mythical character with tusks and horns -- a creature named Osh. Osh is the warden of the Dark Sider King's prison, The Keep. His prime charge is Lady X, a beautiful "young" woman more than 500 years old who was convicted of having created a plague on Earth that killed billions -- though she pleads she is innocent. She is kept alive by Osh's ability to secrete a hormone that affords an entirely undesired immortality. The only problem is that this big, lumbering beast is also in love with her.
At the end:
Afterwards, bedecked in a flowing, white gown complete with ornamental wings, Ariel joins Acada and Driscoll for a picnic by the Sea of Tears. The once elusive Ariel is quite attentive to Driscoll. Osh arrives with his beloved Lady X for whom he has risked death to grant her single wish to see the sun again.
