I believe we do not have any faction like that in the game yet isn't it? Hive mind like ants or AI consciousness like "Mother" from Nexflix.

The closest thing we have is the Harmony, but they aren't a major faction :(

The Umbral Choir are canonically a single entity, though they were "shattered" by the contact with the blight in Coroz.

Meanwhile, the Cravers are a Hive like ants or termites. Note that they are a Hive, not a Hivemind in the Science-fiction sense: They are not telepathically linked, they just work together in a eusocial structure like an insect colony.