>>1825360
>Why are there multiple EU version?
That's just how private servers work. It's pretty common to come across multiple servers ran by different people for these older MMOs, all with slightly (or significantly) different adjustments made between one another.
The official version of TERA is quite literally dead (weird edge-case with the PS4/Xbone incarnation notwithstanding), so if you're wanting to get your Elin fix in, you'll have to choose an unofficial server for it.
>Best EU server
Probably Arborea from what I've gathered, although I do have to preface that statement with the caveat that there /is/ some pretty notable custom content featured on there. Surprisingly high-quality stuff, mind you, though it's not a 100% faithful rendition of Ye Olde TERA as a result.
The other major EU alternative is Agaia; the largest server in the region, and one which had quite a lot of hype surrounding it prior to its release. Opinions on it have since become pretty mixed, however, so I'd still say to give Arborea a shot first.

(This isn't an especially-good screenshot, but HQ for completion's sake: https://files.catbox.moe/623z0x.png)