We would like to be able to cancel orders based on order rules. We have some clients that have orders coming in from woo commerce sites and want to avoid orders from Northern Ireland as they fulfill them from an Irish warehouse. We currently use an order rule to mark them awaiting confirmation and manually cancel them but ti would be good to have a rule to cancel the order directly.
Original comment is best thing to do here.
WooCommerce has the ability to only import orders for a particular shipping zone. We use this for specific countires that are sent to from a different warehouse. Perhaps you could create a new zone that does not include Northern Ireland and setup your Woo connection using that?