I remember looking into it once and the laws for what a foreigner can own are strict. No bow, crossbow, no air rifle if I recall correctly and I presume that it would also apply to an air pistol. One's filipina wife likely could own a low powered air pistol though. By the same token, a spear gun should be illegal if a crossbow is because it's the same principle of stored energy, but I don't remember seeing that anywhere. I don't recall seeing anything about a sling (shepherds bow) or slingshot. I definitely don't recall seeing anything about an atlatl (spear throwing stick).
Ken from the Solar Store (across from Petron in Banilad) can answer this for you. He was the airsoft distributor last year and also he shoots at the gun range in Sibulan and Cebu often.
I spent a couple hours looking and it does appear that airguns are indeed no longer classed as firearms as of 2013. Verify for yourself, I am not giving legal advise. I did my original research in 2010-11. What I can't find anywhere is anything explicitly saying a Foreigner can own, possess, transport or use an airgun, or even an airsoft designed to shoot plastic pellets. And I would be interested if someone could provide a link that was official that explicitly said a Foreigner could own, possess, transport or use an airgun. Marksmanship is a perishable skill. I wouldn't mind being able to practice or to teach others. When I go to someone else's country, I would not assume that I had all the rights that they do. I did see where even after the passage of RA 10591 in 2013 that the Comelec rules still considered airguns/airsoft prohibited for at least a time.
Even if OK, I would not want to be Holding one anywhere near a situation that may provoke Trigger Happy Authorities that are about ( ie PNP, Military on some assignment) In a lot of cases they are very much Firearm Lookalikes. Maybe a hasty/quick action decision from an Armed Officer would result in an innocent victim. Just saying
Possibly if you have the proper permit. I learned more about airsoft than I ever wanted. a 5mm airsoft BB traveling 500 FPS I believe they said it's impact energy was 5.72 joules Austria limits their airsoft to 0.8 joules or about paper spitwad range from a straw. Of course it might have been a misprint.