I am wanting to make some changa with harmala freebase. Can I make enhanced leaf and once its dry dissolve my harmala in water and add that to the enhanced leaf and again dry it out? Would that work?

No, freebase harmalas are not soluble in water. Also, water takes forever to evaporate especially on herbs.

Seeing as only a small amount of harmalas will dissolve in acetone it is best to weigh out both your dmt and harmala doses first and then evap the dmt on to the herbs and once dry sprinkle on the harmalas OR dissolve them together at once.

I would recommend doing the second as the acetone seems to make the harmalas stick even if the harmalas arn't fulled dissolved in acetone.

I normally make enhanced leaf first and then turn maybe half of it into changa, or even make two different changas with different amounts of harmalas in each batch, for a bit of variety.

Alcohol or acetone can dissolve freebase a bit, and as fathomless says, the bits that dont dissolve fully will stick to the outside of the herbs, giving a nice 'sugar frosted' effect. I think this works well as the harmalas vapourise at a higher temperature than dmt, so can tolerate being closer to your lighter flame.