Languages
There is no Horizon canon explanation of what language the Nora or other peoples speak. Skyline makes an inference: the Nora and surrounding peoples speak a language that is close to American English. There is likely some drift over the seven centuries since the first people left ELEUTHIA-9, but probably not as much as might be expected.
Project Zero Dawn brought in scientists, engineers, and other professionals from around the world. The expedited nature of these acquisitions, and what we know about Elisabet Sobeck’s personality and her desire to accomplish as much as she could in the time she had, we might assume led to international agreements of cooperation. Skyline assumes that there are ELEUTHIA Cradles around the world, or at least in the areas where they could be constructed before the war machines would notice.
This international cooperation likely led to the learning modules in APOLLO being multilingual, with the goal of reeducating all the peoples of the world from the same material. Of course, the APOLLO database was purged, but not until after everything was well in motion. This means Zero Dawn would have started with a multilingual approach, intending to restart civilization where they left off, which implies that ELEUTHIA multiservitors were likely configured to use the local language(s). For ELEUTHIA-9, that would be American English, while for ELEUTHIA-01 it would likely be Uyghur or Mandarin (Chinese).
It is possible that, after the APOLLO purge, GAIA could have foreseen communication problems among various groups and taken the opportunity to consolidate the world on a single language. However, even if that’s the case, that one language is likely still English. We know that all the artifacts of the Old Ones are readable and otherwise understandable by the characters in Horizon. A good example here is the Visitor Center in the Banuk lands, and the Montana Recreations displays. GAIA could have reprogrammed those displays to use something other than English, but that seems unlikely.
The second part of Skyline’s assertion about language is that it hasn’t drifted much in the past 500 years. This inference comes from two observations.
First, people don’t seem to have any trouble understanding the grammar and pronunciation of the artifacts of the Old Ones they find — they may not understand what all the words mean, but we do not see them struggling to reconcile their version of words with the ancient version.
Second, many of the artifacts of the Old Ones are audiovisual in nature. Especially when combined with the gradual and continuous discovery of new artifacts, this could have a sort of corrective effect on any linguistic drift. That is, even if pronunciation or grammar began to evolve, the expanding volume of immutable recordings would act as an anchor to coerce it back to something close to the speech of the Old Ones. This presumes a not insignificant volume of rediscovered media of quality equivalent to that found in the Visitor Center. Given the sheer number of phones, digital media players, digital photo frames, etc, in existence today, it’s plausible that any number of them survived a thousand years, especially with the nigh-magical battery technology seen in Horizon.
When building out your world for Skyline, you’ll need to decide how languages are handled. For example, if you start your story with the Nora and your players go far enough south, it’s entirely possible they would meet people who had been released from an ELEUTHIA Cradle in Mexico, and plausibly spoke some derivation on Spanish. Going with a single language can make it easier for your player characters to get around, but there’s also something to be said for the creativity which communication difficulties inspire.
If your game system treats languages as a value-add resource for your characters, consider whether the reduced number of languages in Skyline might warrant compensation with something else. Alternatively, it’s plausible that characters could have learned random languages from books of the Old Ones. They wouldn’t have anyone to converse with in the language, but that’s never stopped people from learning Latin.