I read that Orizaba is an easy climb, really just a high-altitude trek. How hard is it?
If you are in good shape, it can be “easy” on a good weather day and on the normal route. It does stress you as you near the summit due to the altitude and anyone is susceptible to Altitude Mountain Sickness (AMS). I would emphasize that you get in good shape before attempting Orizaba since it can be a long physical summit day.