Replace riven depending on what your loadout. Killing Blow/Amalgam Organ Shatter for the wind-up speed is a nice replacement. If got the wind-up speed covered already via [Swift Momentum] Aura or whatever like [Kullervo]'s passive, I'd put another Attackspeed mod like Quickening. If attack Speed is already covered too by an ability, Status Duration/Status Chance mods(preferably Melee Prowess or Volcanic Edge) are what comes to mind.

Viral Radiation Variant with Shock Trooper: https://overframe.gg/build/493100/
Radiotion and Cold with Nourish: https://overframe.gg/build/499012/