Well, if the Nerevarine can be a mog, he/she can for sure be a teenager as well...
And if you just want to play as a teenager, without adding children npcs to your game world, this is fully possible.
The Mod Play as a Teenager is not dependant on the Children of Morrowind esm. But, you will however still have to download the Children of Morrowind base mod in order to get the bsa-package with the textures and meshes for the Play as a Teenager mod.
Both mods are available from the link in my signature.