Um….yes and yes? Because fiction can be written however you want?
I mean, if your question is what sort of techniques you could use as a writer to stop and reverse a TF in a story that aren’t just the “self-control” MacGuffin, one that I can think of is “The Curse”. The character has to transform unless they accomplish some particular goal, in order to stop or reverse the change (think Beauty and the Beast and stories like that).
And yeah, it’s also definitely possible to have TF stories where people are aware of the changes. I think writers tend to avoid that scenario because you end up a lot more about people’s reactions to the changes and a lot less about the change itself.