No, none of the Meizu phones launched so far are water resistant...

Meizu Pro 5 is not an IP certified device means it is not waterproof or dust proof or even splash proof... The phones that are splash proof (as in the case of minor splashes or protection from rain drops) those phones come with a nano coating which protects the internals of the phone from any damage in case of any slight contact with water... But Meizu Pro 5 (and most other phones) does not come with such nano coating or other protection... So you cannot use it under water... It could damage the internals of the phone... There are just a few waterproof phones available in the market like a few from Sony, Samsung and the iPhone 7 while few others like the Moto G3 are splash proof... None of the Meizu device come with IP certification yet...