I'm looking for a way to combine hosted layers I already have into one large layer with multiple sublayers from AGOL.
The picture below is an example of what I'm trying to do; it was created by exporting multiple layers together from ArcGIS Pro into one layer. Is this possible to do from just within AGOL?
The alternative would be just re-exporting it from Pro, but I have several Domains set up online and I'm not sure how they'd survive the transitions if I went AGOL->Pro->AGOL, and the alternative would be recreating them if I went Pro-> AGOL.

For reference, I need to change various permissions (editing, syncing), as well share a large number of layers with my Group. The first is very doable, just time intensive, and the second one is, too, but having a lot of layers really clutters things and makes it harder to manage.
As a sidenote: Is it possible to better organize things in groups? Like, folders? Or is Categories the best solution?
Thanks!