This activity initially started in 2016 between Vaughan Ling (https://www.heavypoly.com/) and Christian Pearce (https://www.artstation.com/christianpearce) and then quickly spread. The idea being the artists exchange work and the other renders it however they wish.
John Frye’s curated galleries:
2016 (https://www.behance.net/gallery/37853367/The-Great-Sketch-Swap-of-2016)
2017 (https://www.behance.net/gallery/48252623/The-Great-Sketch-Swap-of-2017-%28Updated%29)
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