Are Osymetric chainring and power2max Classic power meter compatible?
Power2Max say:


  Changing cranks or chain rings does not affect calibration. You can also use oval chain rings (e.g., Rotor Q-Rings, Osymetric, etc). Please note: compact (110 mm) aero chain rings (such as Rotor aero Q Rings) are not compatible with power2max Classic, but are compatible with Type S.


So, yes.

That said, does it really matter all that much if they don't? Stages reckon there's a +4-5% error when using them on their power meters, but recommend you just adjust your threshold accordingly. Once that's done you can carry on as normal, the absolute numbers aren't all that important, the zones you define around them are what matters.