https://bugs.winehq.org/show_bug.cgi?id=43781
--- Comment #9 from Sveinar Søpler cybermax@dexter.no --- (In reply to Storm Engineer from comment #8)
So is there any workaround for the time being? Any way to force-compiling those shaders before playing?
Not atm.
There is a lot of progress with Steam and "Proton" + that Steam has some vulkan shader cache thing where you download pre-compiled cache. Not tested this myself, but in theory it should be something that over time will fix stuff like this.
DXVK has its own implementation of vulkan cache possibly for this purpose (or some time in the future some implementation of this with Proton).
You could give DXVK a whirl with Overwatch tho :)