Multiple world saves on Bedrock Realms [Java Parity]

In Minecraft: Java Edition, you can have up to three worlds loaded into one Realm. This is not the case, however, in Bedrock Edition. My realm’s world is too big to download onto my device as a normal world, and I was hoping to be able to add another world when the Caves & Cliffs update comes out because of chunk borders, simulation distance, and a lot of other things that could possibly affect my world and gameplay after the update. Since I and everyone I have invited to my realm loves the old world, I was hoping to be able to add a second world and use the /transfertoserver command to be able to link the two worlds. I would really love for this to come out with Caves & Cliffs, as that is when I am planning to make the new world.