And you ARE allowed to have two different accounts in the same world, and could thereby play both an Elf and a Human in the same world. The Game Rules for Elvenar are not the standard boilerplate that you may have seen in other InnoGames products. Notice how carefully they've threaded the needle regarding multiple accounts. See
https://us.forum.elvenar.com/index.php?threads/game-rules.701/
If a couple only has access to one computer, by using DIFFERENT browsers both accounts can be logged in on the same computer, in the same world, and just pass the keyboard back and forth. The potential for abuse is obvious, so in many games multiple accounts in a world are simply forbidden, but Elvenar is inherently resistant to pushing/gifting/using mules.
You WILL have to be VERY careful to avoid even the appearance of "pushing," which is using mule accounts to feed a master account. So long as BOTH of the accounts are pulling their own weight you'll be fine, but you should be SCRUPULOUS about equal value trades, and reciprocal contributions to each other's Ancient Wonders.