Hi there, Linux user here.
As I get it, d912pxy is a wrapper that turns DirectX 9 calls to dx12 calls, which can improve performances in some cases.
Here on Linux, there is not DirectX, it’s Microsoft patented; we got the choice between OpenGL & Vulkan API. So, to play games, I’m using a wrapper “DXVK” that turns dx calls to Vulkan.
Now does it improve performances ? On Linux for sure. On Windows ? I doubt about it.
I made a thread about DXVK use on Windows, you’re welcome to read it, but afaik, windowsians who tried didn’t get any perf improvement.
Also, SWL can be runned w/o crashing, but is awfully sensitive to drivers used. I haven’t had a crash using nvidia drivers 460.xx, but the game would crash/freeze if I use nvidia drivers 470.xx
TL; DR: Dont expect miracles by using d912py, game has bad code quality, only Funcom devs can change that.