Mingling and intertwining of different cultures has always happened in the art world. Without this process some of the most beautiful and influential art pieces may have never been created.
Tibetan culture and some of its aspects has been seen paired with aspects of the Chinese cultures in artwork. As time had gone by the Buddhist culture had been seen in China. In the Chinese culture the Buddhists were seen as enlightened and depicted in paintings as such.
Intertwining of cultures has gone on for thousands of years. This may be why we have seen bits and pieces of different cultures mixed together throughout various paintings.