Hello Shaun,
If I hit Play in the viewport, it’s exactly like in Editor viewport, totally fine.
Since I don’t have any Game Overrides in MRQ settings, I think you talk about Game Settings (in the viewport settings → Exposure section → Game Settings unchecked) ? if so, I unchecked it → Editor’s viewport is darker, and everything looks fine when playing in the viewport, it becomes as balanced as the Editor viewport with Game Settings checked.
No autoexposure at all.
About scalability settings, please check below a screenshot of the current settings.
Hmmm I can’t think about any repro steps tbh … the only “fancy” thing I can think of is that I use Ultra Dynamic Sky - not sure if that helps though.
Thanks again.