We do have ensemble models. Something like

    model = NaiveEnsembleModel([model1, model2, ...])
    model.fit(my_series)
    prediction = model.predict()

Will return an average prediction. Look at RegressionEnsembleModel for an ensemble model which uses a regression model to learn how to combine the individual forecasts.

At the moment Darts doesn't have hierarchical reconciliation methods (if that's what you meant), but it's on the backlog :)