afaik no, but I never tried doing that. Maybe it is possible but you'd have to either write a little complicated script in AutoHotkey or study KF2's KFInput.ini file.

need to ask. did they implement a way to sell or bind different key to the weapons u spawn with, like regular knifle and pistol? is that last on list "allow swap to 9mm" if it is, is sad not to see same option for knifle. i alwas hated that i need to press 3 x3times or 1 x3-4times.