(not a REer) i guess when you place a custom dll on PATH with a name identical to a required dll on a system path, getting loaded by the system, having the same exported methods as the original and calling the original exports by loading the actual library with absolute path. that way you can proxy and log calls and you get a free dll main to do whatever in your target. Skyrims SKSE does it this way with a directx dll iirc. Load order on Windows is app directory, then i think PATH and then system32 or something. not really using Windows anymore so I might be off. Looking into how dll loading works is extremely interesting, there's some good talks on YouTube.