Like what other people have said, try to EQ down the 5khz to 6khz area and maybe reduce abit of the 8khz as long as it still sounds normal it should be fine.

Another way it to add toilet paper(try 1 ply at a time) untill the sibilance is subdued enough. This has the downside of trapping energy and giving more sustain to everything which if overdone can sound quite wonky.

Cables wise hard to rec since I donno how Venus reacts to cables but based off guestimation either a OFCopper cable if you prefer a heavier and smoother presentation or a silver and graphene cable if you prefer to keep the speed. Try to avoid OCC copper and silver plated copper(esp this) as those tends to highlight the upper mids and esp depending oh how the SPC is done can get very aggressive.

Personally I would try the toilet paper method first since that cost very little and has immediate effects since EQ is a pain unless you use only the Venus. Cables wise I would hold back since Ive been told my sensitivity to cables is on the higher side and cable swaps do nothing to some.

I donno much about mixing as well but the mixed vocals sound quite compressed and processed. The unmixed ver has proper vocal intonation as well as the instrumentals sounding correct.

But I guess drumbeat go burr is want that guy wanted.