The UE Render Grid Plugin was one of the tools I product managed and prototyped while at Epic Games. I designed it to allow users a UI friendly way to create infinite variation while using the power of movie render queue.
UI navigation guide:
https://dev.epicgames.com/community/learning/tutorials/BEmk/unreal-engine-render-grid-navigation
UE Fest Intro Example
Aiden Wilson giving an great overview on how to use the toolset