You really need to have a closer look at this thing, because it can definitely do all of that, and much more.

Earlier today I saw a video (sorry, lost the link) of an AI editing program (still a prototype). It generates layers of a scene in place, say sky, mountains, rivers, foreground, etc. each of which would be individually manipulated. Next the program seamlessly blends the layers. The host then continued to add objects/subjects and through "in-painting" made all of it blend into a single coherent scene.

This kind of capability is close to being released. This year.