One thing of note, since this adds missing chartdata difficulties to the metadata difficulties for that variation, this means that stuff like picospeaker will show up in the difficulties, and it'll be saved as a playable difficulty?

I think instead I'll just make it add the difficulties to the difficulty toolbox instead, and later, I can add a button to add/remove said difficulty from the metadata, and add some kind of visual in the metadata toolbox.

Until that stuff, there'll be a few cases I'm sure of someone complaining why their difficulty shows up in the chart editor but not in freeplay or whatever, because the chart editor does not indicate that the difficulty isn't in the metadata.

It's time

The name of the PR confuses me
What's the actual purpose of this PR now that variations do seem to fall back properly?
Is it about making Pico's chart accessible in Stress, for example?

The name of the PR confuses me What's the actual purpose of this PR now that variations do seem to fall back properly? Is it about making Pico's chart accessible in Stress, for example?

No, that's the new draft pull request. This is just the variation fallback now. Didn't make much sense to use this branch for the new stuff anyway.

Basically, this is just hopefully fixing a few edge cases where the main variation of a song isn't called default