I've dove open circuit to wrecks in varying currents. Max depth for me has been 100 meters. An OC diver can swim about 0.5 kts, with a good scooter, about 1 kt. The high current dives can be arranged by arm over arm with a planted anchor. Moving off the line in 3kts or greater will not allow return to the anchor line. The other technique for OC targeted dives is to be dropped off upcurrent. This saves your arms, but you might end up "flying" by the target at speed. If lucky, you can head for a protected wreck assembly that shields you from the current. Moving upcurrent is essentially not doable above 4 kt current. The issue is the bottom type. Even if sandy, 3kt currents cause "sand storms" at the bottom, limiting visibility.
Wreck diving in high current is brutal. I've had marker buoys 30 inch diameter be dragged all the way to the bottom, collapsed by water pressure, submerged by current.