Right, basically all EMV cards are ready. You just need one that has some offline tolerance, as there are limits on both the amount and number of consecutive offline transactions. I believe these settings can be updated on the chip, i.e. your bank will tell you to go to an ATM perform any operation to make sure it's up to date.

Payment terminals might be trickier as we've observed during outages that they currently don't fall back to offline transactions. But their software and business rules can obviously be updated.