Whats gonna happen with same nicks if there are some in both servers?
This is not a merge yet. This is update of GF server into H5 chronicle. I think merge will be about February. GF server needs about 1 month to adapt to H5.
If you have character on both server with same nickname, the character which has higher lvl will have the nickname, other one will be names like name123259 and you will need contact support to change it. If lvl of both characters are same, then character with higher xp (or SP???) will have nickname.