Luckily there isn't such a phenomenon in this franchise but it's actually surprising that no one has gotten the idea of genderbenbing either Littlefoot or Cera and then writing a steamy romance between them.
I wouldn't know about lucky, since I love me some queer stories and seen many done well (Though I can understand a lack of interest in romance. Even in some future fics I have in mind, there are characters many of whom I fav I keep unmated and childless), but anyway...
I've already seen some shipping of Littlefoot and Cera as their current gender identities, so no gender-shifting needed. Formula: rivalry+characters of near age to one another=shipping fuel regardless of the gender identities or sexual orientations involved.
Like in the Seven Hunters? I've seen your reviews on Fanfiction and it seems you like the story quite a bit. 
I still mentally default to their birth names when identifying them. Even when they used their sharptooth names, it can still throw me off. It's how I began to know them and it's how I still know them. It's kind of like hearing their kid voices have imprinted in my mind. Even when I read fanfics where they are adults or even elders, they still speak with prepubescent voices in my mind.
You could always name OCs those original names as a kinda shout out if they interest you enough.
