I reached level 30 around an hour ago, and found out that I can't use any of my Pokemon from Kyoto in this new realm (Jataro), including the Pokemon that i got from eggs unless I'm a certain level (e.g. I can't use Moltres unless I am level 48 when I'm only level 30) My suggestion is that everyone can use their Pokemon from eggs on either realm and still gain XP to level up.
That would be stupid since a lvl 100 will be easier to gain xp . You'll be up to lvl 50 way too quickly