I will discuss two scenarios that give rise to QCD axions with large flavor-violating couplings at tree-level. The first scenario is a class of generalized DFSZ models with PQ charges compatible with a 2+1 flavor structure, in which the flavor misalignment are treated as free parameters and control both diagonal and flavor-violating axion couplings. This structure allows to construct axion models that have suppressed couplings to nucleons and electrons, thus avoiding the SN/WD constraint. The axion can be as heavy as 0.2 eV and therefore be tested at the next generation of helioscopes. In the second scenario the PQ symmetry is identified with a U(1) Froggatt-Nielsen symmetry, so that axion couplings to fermions and photons are related to fermion masses and mixings. Both scenarios can be tested by precision flavor experiments like NA62.