I received this image from a Zen Center in BC Canada. The Nun who gave it said that this is an authentic portrait of what Shakyamuni Buddha actually looked like. You can see that he is wearing baba style earrings, and has a Nepalese / Mongolian face.
Underneath in Mandarin was written :
“This is the only true portrait of a Sakyamuni Buddha during his lifetime.
“Is one of the ten disciples of the Buddha Punna Venerable. Blessed One was 41-year-old when painting.
“Today the collection in the British Museum, is considered a British national treasure.