Any LP plug-in must add latency to work properly. It is not a matter of CPU, it is a matter of time. The plug-ins need to see the incoming data before performing LP processing. To do this, the plug-ins must buffer the data. This is what causes the latency.
The plug-ins are designed primarily for mixing and mastering where latency would not be an issue. It is possible to eliminate the latency by changing the Precision setting in the Expert section of each plug-in to Non Linear.