Not impossible, but I think that is unlikely has kbin has a totally different backend and also additional functionality that is not available in Lemmy apps.
The lead dev of kbin has said he's evaluating implementing the API.
kbin has a totally different backend and also additional functionality that is not available in Lemmy apps.
This doesn't make it less likely. They can implement the lemmy api for compatible features and add their own api (or more likely use the masto-api) for the other features.