All supported play styles offer Easy through Expert; Drums also support Expert Plus.
Core difficulties
Easy, Medium, Hard and Expert are officially confirmed. The publisher has not yet documented how note density, chord use or lane complexity changes at each step.
Expert Plus
Expert Plus is confirmed specifically for Drums and is presented as the level beyond Expert. Double-kick hardware is available, but the official pages have not said whether it is required for every Expert Plus chart.
Per-song ratings
No song-level difficulty tiers or instrument chart ratings have been published. The song database therefore does not show inferred difficulty values or pretend that every confirmed song has every chart.
Calibration and accessibility
Detailed calibration, assist options, no-fail settings and accessibility modifiers remain unannounced. Those systems can materially affect difficulty and will be added only after official documentation is available.