What's the Difference Between a Regular and a Vocalized Form?

The name nasalization isn't really consistent in what it means across the board. For a voiceless stop, for an unvoiced stop like P or T or K, it means that sound becomes voiced. There's others, like M turns into like a nasalized V. Leonited is often turning things into fricatives, but it's like, it's a little bit all over the place.