Can one sell a theme with multiple Child theme variations?

I have created a theme and ready to create some demo content for it, is it allowed to include several different child themes to vary the design since it would be impossible to make all demos with one theme for this particular theme.

You need to check with Envato but I doubt it very much as this would require the parent theme also i.e. they’d need to buy both versions (hence hwy authors add demos to big themes)