I’ve researched many times when I had the same idea. Sleeving is not a good option for our N54 engines, as timing will never be ok despite the best racing fuels, since because harmonics in the engine won’t be the same like stock block.
You realize just because the DME *thinks* there's knock doesn't mean that's actually the case right? Especially with upgraded internals
There are hardware and software fixes for false knock. Otherwise built motors would never make the power they do.