Сработает первое и на этом проверка правил закончится в цепочке для этого пакета/соединения. Если он удовлетворяет условиям правила.
"When processing a chain, rules are taken from the chain in the order they are listed there from top to bottom. If a packet matches the criteria of the rule, then the specified action is performed on it, and no more rules are processed in that chain (the exception is the passthrough action). If a packet has not matched any rule within the built-in chain, then it is accepted."
https://wiki.mikrotik.com/wiki/Manual:IP/Firewall/Filter