Rocket League and Unreal Engine 5
Reference
For a list of sources, qoutes and other related content, see the UE5 reference page.
After rumors following the leaked plans for Rocket League, that it will be transitioned to UE5, Devin acknowledged on Reddit that this is an ongoing project for Psyonix.
What the effects are for Rocket League map making are not clear until Psyonix shares their plans. For now, you don't need to learn UE5 as it will take some time before they finish this long-term project.