https://bugs.winehq.org/show_bug.cgi?id=42856
--- Comment #10 from Hugo "ThePooN" Denizart thepoon@cartooncraft.fr --- In this blog post, I detailed how I was able to reduce the osu! audio latency while using PulseAudio and winepulse.drv with a patch. I haven't tested it with osu! and it is in no way up to anyone's standards, but I'll still leave it here.
https://blog.thepoon.fr/osuLinuxAudioLatency/