You can create morphs in the highresolution figure and save and load the figure with all the morphs in tact. Everything still works as normal. Only thing is that if you save with the morph set to 1, the figure loads it as the zero figure (morph dial at 0, but morph applied). The subdivision still worls, all other morphs still work.
I GoZ genesis in high res, applied a nose morph and got the morph in Poser. Then I saved and loaded the figure after restarting Poser. When loading the figure, the DSON importer worked as normal.

It is another matter whether you can save the morph as an injectable morph for other figures. I think so, but I am not sure what implications and restrictions that would have
To have it play nice with the other morphs you probable have go the DS route.