Reliable reproduction: Heroic Sludgefist, graphic settings on 7. Triggered in LFR too, but it took longer.
MacBook Pro (15", 2016)
macOS Big Sur 11.2
Processor 2.7 GHz Quad-Core Intel Core i7
Memory 16 GB 2133 MHz LPDDR3
Graphics Intel HD Graphics 530 1536 MB
Razer Core X enclosure
eGPU AMD Radeon Vega 64
Secondary Display GIGABYTE 27" QHD Curved (G27QC)
EDIT: provided some context in the other thread: Freezing of screen (GPU crashes) retail and classic - #102 by Bellexandria-exodar