Yes, but they can sometimes do similar jobs.
A multiband compressor uses crossovers to split the audio into two or more bands. Even though the crossover points may be adjustable the response shape of the crossover filters usually is not - and they typically have a relatively shallow (6-24dB/octave) slope. For that reason it is not always possible to use an MBC to control a resonant bass note, for example, without also pulling down some of the sound around it. In other words, an MBC works over somewhat broad ranges (Bass, Mids, Highs, etc.) but still offers more control than a mono band compressor.
A Dynamic EQ, on the other hand, usually has parametric filters where the frequency, slope/“Q”, and gain are all independently adjustable - just like a typical Parametric EQ - but the gain can be controlled with a sidechain level detector. It’s an MBC taken to the next level. You can “zero in” on exact frequencies and bandwidths and compress/limit/expand as required. When used properly it is VERY transparent.
A plugin such as “Studio EQ” can be automated to give a “dynamic EQ” response but it can take a lot of automation curve tweaking to get it right.
There are dynamic EQ plugins available as third-party VSTs but the good ones are expensive. It seems like CB6 has enough routing capabilities that there should be a way to “make one” using what we already have - and just the way we want it. I will keep working at it and post if I find a means.