This bug is a little weird. It may have been canonized by Dragonborn.
The Grand Staff of Charming has the wrong spell effect; it uses Calm instead of Pacify. It was originally intended to use Pacify, as the Staff Enchantment effect for Pacify is known as "MassCharm" (and that's also the internal name for the Grand Staff of Charming); however, this Staff effect is used by a mystery item instead, thus giving it the appearance that the correct effect has been applied.
This is weird because the Grand Staff of Charming cannot be crafted at the Staff Enchanter, even if you know Calm or Pacify. It doesn't have a recipe. It also has the same description as the Staff of Calm, but that's because the description for staves is picked by the enchantment.
Compare this to the Staff of Thunderbolts (incorrectly assigned to use Lightning Bolt instead of Thunderbolt), which the patch fixed. Absolutely zero items use the Thunderbolt Staff effect without the Unofficial Skyrim Special Edition Patch, though I presume that the staff was only fixed because it had a Staff Enchanter recipe that called for Thunderbolt.
Is this considered a bug, or something intentional?
Issue Data
Issue #34592: Grand Staff of Charming uses the wrong Enchantment, and cannot be crafted