A collated list of the various subtypes introduced by Oriental Adventures and converted to 5e. More for my reference than anything else. Will be updated as I use it.
All kami and oni are yokai, but not all yokai are kami or oni. In terms of my D&D campaign yokai tend to be neutral fey and all undead. Any reference to spirits refers to yokai. Any reference to shadowlands and taint refers to oni and some yokai.
YOKAI
Yokai details here with examples.
KAMI
Kami details here with examples.
ONI
Oni details here and examples.