If server transfer was available, possible to transfer to another region?

as the title said

Doubt it.

Even with Blizzard and their character transfer services, you would only able to transfer between the region you played on. You were never able to move between different regions.

AGS promised regional transfered back in New World and then back tracked on their promise and only allowed transfers within the same region.

So don’t expect anything like this ever happening in Lost Ark now or in the future.