If the low-and high-level methods correlate, the model does not need to learn as much chemistry, as the fast method captures most of it. While the combination of ∆-ML and NN is uncommon as the improvement is not marginal and ∆-ML is less practical for final application (e.g., MD simulations), we only use it for consistency and eventual comparisons with our previous studies. Therefore, when ∆-ML is used, we used GFN1-xTB as the 'low' method.