Patched DXVK binaries.
DXVK: https://github.com/doitsujin/dxvk/releases
Async-pipeline-patch: https://github.com/Sporif/dxvk-async
The Async patch (with further adjustments) has already been worked into the custom Wine version of GloriousEggroll since Proton-5.8-GE-1-MF.
https://github.com/GloriousEggroll/proton-ge-custom/releases
To use the async patch from within the custom Wine version with Lutris: go to System Options, simply set Environment Variables to DXVK_ASYNC 1
To visually reflect the change: DXVK_HUD fps,gpuload,pipelines
For more detailed information see the links above.