About half of this whole idea probably means they just need a non-‘vampire’ name. But I’m demonstrably terrible at coming up with names for things.
Spherian vampires have been around since at least a millennium ago, probably longer; the uncertainty is because they tend to keep to themselves, and most of the (surprisingly large) more metropolitan population don’t feel the need to advertise the fact. How they came to exist is a subject of great debate with no solid answer, although there are several (generally more powerful) specific families which are agreed upon as being the ‘original’ bloodlines.
If it’s possible to convert a pre-existing standard human to a Spherian vampire, it must take some extraordinarily long and phlebotinum-filled procedure; nobody seems to have happened upon anything of the sort, despite any efforts to do so. They aren’t a proper seperate ‘species’, possibly apart from some weird metaphysical senses, it’s just that the markers for vampirism seem to be amazingly dominant. (A rare mutation exists which does create a child akin to a half-vampire/dhampyr, but the emphasis is on rare. Even once you get past that, any such individual would be hunted down. There’s a lot of superstition surrounding them, much of the ‘kill them and gain amazing power’ type.)
Spherian vampires are immortal; age has little to no meaning to them, and they have some limited form of healing factor (much less of one than Kunming Device Immortals or Janelle Donovan, though). They also have very good all-round stats to start off with, and limited shapeshifting, especially your semi-classic ‘horde of bats’ mode. Some of the ‘original bloodline’ types also have true forms which you may behold and despair… which commonly point at the ‘different species in some weird metaphysical senses’ bit, possibly some kind of eldritch abomination influence way back when. All of these abilities are easily lost in direct sunlight or lengthy lack of blood/emotion/generic life energy apart from the good stats and super-long lifespan, though.
They seem about as likely as your average KMVian to have an extra ability on top of that. These usually are much less affected by basic meteorology.
Much of the reason they stay out of the spotlight, though, is also that – as a society – they tend to be hidebound and legalistic. This is only a general trend, mind you; Jacob Schwarzwald (the only major character who happens to be one) is sufficiently laid-back to near completely horizontal. …Of course, they also kicked him out, but I’m pretty sure that was for other reasons.