There are similarities between the games, which is not surprising as they are developed by the same company, but there are many differences. If you know how the GF UI and short cuts work, you'll be able to get used to EE fairly easily. EE is also mainly a PvE game, but the PvP has little affect outside of arena (Unlike GF where some end game PvP sets are so OP in and out of arena). The differences are mainly in what you need to accomplish to play the game (Ex: Joining a guild is practically essential in EE in order to accomplish many necessary things from a low lvl, whereas in GF guilds don't really matter aside from the social aspect until end game with guild wars)
And while the human and halfkin races indeed look like children, the Ursun (giant bears), the Zumi (mice), and Anuran(tall lanky frogs) look nothing like kids.