Not polymeter, polyrhythm. Where you can compose different subdivisions of the same meter, i.e. being able to articulate between 3 beats per bar and 4 beats per bar over the same BPM. Or to have two instruments playing together in polyrhythm, causing them to syncopate, for example.
Does the XY contain such a functionality? If so, how do?
What I observe currently is that the time signature setting resides in the project configuration page. IMO that setting should be considered a global time signature, and each track should have its own time signature setting, subdividing the global differently if changed.