I don't know of any other plugin that's set up
exactly like this one, certainly nothing bundled with SONAR.
However, the upward+downward compression technique itself is nothing new. It's just traditionally been done with two compressors or parallel compression. Any compressor that supports negative compression ratios can do upward compression. Unfortunately, none of SONAR's bundled compressors do this, AFAIK.
In practice it isn't done all that often, because unless your tracks are really clean it'll also bring up your noise floor. What's far more common is parallel compression, which is a form of upward compression that's less likely to hurt your SNR.