You wouldn’t call a person a dwarf, period. So don’t do that. If you ever meet a little person, they’ll probably refer to themselves as a little person. You should just follow their lead
A dwarf planet is not a category of planets. It is a category of sub-planetary objects. This is how the term “dwarf planet” was adopted by the IAU in 2006. It did used to mean “type of planet”, but there are just too many of them, and they’re really too different from planets, so it literally does not mean that anymore. At least to astronomers.
I’m not going to argue with astronomers about how they define planets. I do my job, they do theirs!