I believe it's been said that it can be topped with virtually any product one desires.
I would assume if the topper of choice does not have any abrasives in it itself, that it should be able to be deposited on top of Essence without greatly harming the Essence Coat and filling properties.
Since Essence leaves a "clean prepared easel" for coatings to adhere and bond, one then should have absolutely no issues with waxes, or sealants either.
Let's say something like Collinite 845, or WGDGPS 3.0 or other products not loaded with cleaners and such.
That then the results of behavior and qualities of the topping product will likely dominate.
Most would probably say and suggest to "keep it in the family", with other products from Carpro (Reload or Hydro) or other similar type designed products perhaps as GTechniq C2V3, etc.