I cant find one that isn't littered with viruses

I've seen it in speed runs and I'm not sure how they charge the dash in place, just spam back and forth then attack? Or is there a certain amount of times you have to run??

I'm interested in getting into speedruns and wanted to do this and Castlevania 64, I've emulated both using a 360 controller and own a console but strongly prefer the 360 controller to the n64. For official any% speedruns is it legal to use emulators or non-n64 controllers?