Does Rewind work with MPE?

Rewind records MPE properly. Getting it back out depends on your DAW.

Logic Pro handles MPE files well. Ableton loses MPE information, and Bitwig truncates MIDI CC data, when you drag a capture in.

The problem is in how those DAWs process the dragged file, not in what Rewind captured. If you're working in MPE, Logic is currently the safest destination.

Other MIDI quirks worth knowing

On Windows, enable Shared MIDI in Settings → MIDI. Windows doesn't share MIDI between applications the way macOS does, so without it Rewind can't see your devices while your DAW has them open.