There’s no official English website for this game as of December 2015.
project exa
TERA 2 rumors resurface thanks to rediscovered character renders and a Project EXA interview
Even though TERA still seems to be going strong for developer Bluehole Studios, that certainly doesn't mean the studio can't keep working on something...
Bluehole Studio artist posts Project EXA renders
What is Project EXA? We don't know at this point; all we know is that it's something Bluehole Studio has been working on since 2014...