How to combine multiple tiled landscapes?

I’ve been using world composition with imported tiled landscapes from world machine, and it works great as long as i only use a single import…

But i want to import multiple different tiled landscapes with varying styles of land because some parts of my maps will be vastly different than the others.

I can’t figure out how to connect them once i import them. I can place them next to each other, but i cant edit their landscapes simultaneously to sculpt them together. Obviously if i add a single landscape via the “add adjacent landscape” feature i can do that, and it works but that’s not what i need to do.

Is it possible? Or is the only way to import a single tiled landscape?