A wife was living separately and considered nusyuz when her husband died. Does she still inherit?

Yes, as long as the marriage has not ended, the wife remains an heir even if she was disobedient (nusyuz) or living separately. Nusyuz affects the right to maintenance (nafkah) while the husband is alive, but it does not cancel the right to inherit. What decides it is the status at the time of death: was she still his lawful wife, or had she been divorced and completed her waiting period (iddah)? Angry families sometimes try to push such a wife aside. That is not permitted, because heirs' rights are fixed by Islamic law, not by feelings. If the marital status is disputed, for example there is a claim of an unregistered talaq, leave it to the Syariah Court to decide on the evidence. See nusyuz.