I updated the game & verified once.
Found a setting that works for me and DX-12 is a must for smooth running. (AMD/AMD PC), MSAA OFF.
Running 144hz/144fps cap in drivers with the game set for triple buffering "V-Sync" (crossfire, identical GPUs, setup).
Was doing CTDs with the in-game "V-Sync" off also, not really needed since my drivers are set to Enhanced Sync.
No specific spot or event to pin it on, happens in game, stationary or action, even in video intros.
DXMD.exe
1.19.801.0
59140c32
DXMD.exe
1.19.801.0
59140c32
c0000005
00000000009fd49e
1bc8
01dbc7a5d3e897c7
B:\GOG Galaxy\Deus Ex Mankind Divided\retail\DXMD.exe
B:\GOG Galaxy\Deus Ex Mankind Divided\retail\DXMD.exe
27ca31a2-4cf9-47dd-9c24-4307118f061e

YouReekAh ! I found something...

Setting the shortcut to Administrator & No Win 10 interference does not set DXMD.EXE to the same, because it's in another directory. I set DXMD.EXE to Administrator and No Windows Optimization and it seems to run somewhat smooth at least 4 hours. Had 2 instances when it quirked and wanted to plotz, but it recovered.
All in all, I am glad it works with Crossfire too. Seems to perform well. Can't say it's a solution for now, but it reminds me of Cyberpunk 2077, that's how I finished my first game there (on Win 7 before devs. nuked that option).