She was free of the influence of the dragon of the moon and with no mind gem in the 1st Annihilation event. I don't think she was too impressive in that.
I think Oracle faced off with one of them in War of Kings I just can't remember if it was Moondragon or Cosmo & Mantis
Moondragon is intended to be powerful though I have no doubt if a writer was to write her in an Xmen book shed be on par with Xavier just because people tend to forget minute details and power boosts.
Much like Psylocke vs Shadow King in Remenders X-Force which is like the complete opposite of Psi War despite being homage to it