Need tips for switching back and forth between Rock Band 4 and Fortnite Festival

I prefer Rock Band. I have nearly a thousand songs on RB4, but have found recently that FF is a fun source for supplementary free songs too.

Switching between the two feels like it takes like 20 minutes of adjusting to the different hit boxes/timing expectations to be able to play at my normal level and that 20m on either end is pretty miserable and annoying.

Has anyone figured out a way to adjust more easily between the two? Is there a reliable way to tweak the settings so they'd just feel the same ignoring their different built-in sync methods?

This question feels more specific to the Rock Band crowd than the FF crowd given that we're the ones still playing a game that came out 10+ years ago and isn't even available for purchase anymore. Of the two groups, I think more people familiar with my plight are in here than the FF Reddit.