Stress hardiness– durability / resistance / ability to absorb high levels stress / ability to maintain equilibrium even in stressful circumstances /

Clearly you are free to make your own decisions and take into account the considerations that you choose but as a mother-tongue speaker I would avoid the word ‘hardiness’ point blank for the reason that the only context I can think of it (or something resembling it) being used is ‘foolhardy’ (presumptuous, unduly bold)