bitflipper
Sounds like a great experiment. Be sure to post both versions so we can hear and compare them!
 
Saturn might also be a candidate for duplicating the Mixbus effect.

Never having used Mixbus, I have no idea, but somehow I doubt Saturn is very good for this purpose (I do love it to pieces, so don't mistake my comments for dissing Saturn).
 
The most righteous vintage fairy dust I have come across comes from using Nomad Factory plug-ins.  A lot of people have most of their gear courtesy of a 99-bucks-for-everything sale that has run a couple of times in the last six or seven years.  There are three plug-ins in particular, the Analog Signature Series, that are true magic, IMO.  The key to success is to not over drive them or they sound like junk.  The NF Pulsetek EQ is another total gem.  None of these effects do any kind of track cross-talk magic, so maybe the results are nothing like Mixbus.  But results there are, and to my ears, the results are quite lovely.

I am someone who has used both Mixbus and a plugin that sounds like the Pultec EQ for example. I use the Nomad version of that. They are two different things. Mixbus sounds like a Harrison console and the Pultec EQ sounds like the outboard gear. No reason why one cannot be used inside the other though.  I have just got 32C and that will be a nice channel strip on its own but with the Pultec inserted there will only be more colour and options. 
 
I do like the sound of the Nomad Pultec EQ though. It seems to solve issues even with no eq setting being used! I prefer the limiter off and it does change gain a little and needs to re-calibrated level wise coming back out. It seems to smooth out anything slightly harsh. The M32C EQ would be the closest thing to the Pultec EQ in the channel strip. The both work over different parts of ranges etc.