TMVA application on MC systematics

Dear all TMVA experts,

I have a question on using TMVA applications on all the MC systematics.
As the MC systematics(ups and downs) should be given to HistFitter tool to set the limit, is there a way to apply the obtained TMVA models to all the MC systematics so that they can also be through the TMVA cut just like nominal value?
(as nowadays there are 50 different systematics in the MC, apply the obtained TMVA model on them one by one is not that efficient)

Many thanks!

@moneta, Could you have a look at this?