Is the Hamiltonian of wannier90 an orthogonal basis？

[woyolo990422]

I want to know whether the Hamiltonian of wannier90 is an orthogonal basis. This is different from the Hamiltonian of lcao of some DFT software, such as the Hamiltonian calculated by openmx and abacus (they are non-orthogonal, and the calculation of the energy band requires intersection After processing by stacking matrices, it can be diagonalized normally)，In particular, the orthonormal basis Hamiltonian may be applied to some methods of machine learning Hamiltonian (DeepH, DeepTB).