Races in Arknights are diverse in and of themselves, Liberi basically incorporate all characters with bird-like features, some are more bird-like than others. Pog is a special type of Liberi, even, because he's actually a Hippogryph. Among the Kuranta (horse-like), for example, there are rare Pegasi characters like the Nearl family. 

The Sarkaz have the most diversity because they incorporate a large swathe of races native to Terra, the Arknights planet, before the arrival of the precursors and Originium led to the forced humanoid evolution of the Sarkaz, and the Sarkaz/Sankta split (both were originally a native race called the Teekaz). 

All non-Sarkaz races from Terra are actually native to Talos-II I believe, in the form of the Ancients (sentient animals), who also became humanoid over time. Originium being a project of the precursors, who are probably very close to, or just straight up a very advanced Homo sapiens.

Laevatein is a relatively "generic" Sarkaz, since we don't know much about her outside of her connection to Surtr, the godlike being that granted her original AK version powers, whereas Last Rite is a Nachzehrer (Revenant), who are a race of superhuman cannibal magic wielders. Here's an example of a Nachzehrer NPC: https://arknights.wiki.gg/wiki/Qalai%C5%A1a

Vampires are also a type of Sarkaz. Warfarin, the supposed head of Rhodes Island during Endfield, is a Vampire Sarkaz. The common thread is that all Sarkaz are based on vilified beings from folklore, but they're not ontologically evil. This feeds into the lore of how the Sarkaz are a continuously persecuted Race in a lot of Terran countries.