Landscaping help: what to plant?

I’ve got a fairly large bed in my backyard that is staggered with little Jim magnolias and azaleas. It’s fairly sloped and most of it gets a good amount of afternoon sun. There is shade in the morning. The magnolias do well. The problem is my azaleas often wilt in the summer and I’ve had to replace several if I don’t put extra water on them. I’m looking to replace the azaleas with something that handles sun and drought a little better. I was thinking of something like a grass plant.

Does anyone have any experience with grass plants that can tolerate hot afternoon sun but also thrive in partial shade? Any recs? TIA