Mario Sports Mix good game?

[MnSG]

Not to mention facing people you just defeated in the previous matches

If it was Yoshi, Toad, or Slime, that can be understandable. Additionally, the White Mage's alternate outfit does tend to make her look like a different character. The same can also be said for Ninja and Black Mage.

For everyone else, it's just plain strange to face them again after beating them previously (except for Moogle and Cactuar, which are also a kind of species).