Upon running NN-MDs with the two NNPs, around one-thousandth structures were collected as seeds for further DFT simulations. These were further selected as follows: (i) one third of structures whose symmetry function values are not within the range of the current dataset (i.e. extrapolations) (ii) by comparison of the two NNPs runs, when the differences between two predictions (energy and forces) are larger than threshold (~5-10 × RMSE). The latter strategy allows identifying structures beyond the explored structure space as interpolation. Then the dataset was updated with the DFT values for these newly calculated structures. Finally, to ensure the robustness of the potential, NVT simulations for models under extreme conditions (at least 1100 K, 1 ns) were performed. These models include: (i) a Cu slab with 3240 atoms generated by removing all oxygen from an Cu2O(111) pristine system, (ii) for Cu2O, a Cu1415O784 cluster, and (iii) for CuxO, a slab of OD-Cu (Cu444O56) from our previous study .