I airsofted (as well as a little .68 paintball, and more .43/rap4 paintball) for a few years, so if anyone has questions feel free to hit me up. I was the secretary for what was the countries largest club at the time, and dealt with handling club requirements for import permits etc as well after the recent law change.
Legal requirement for owning an airsoft gun: be over 18.
Safety requirement: ANSI 1337/Z83 safety glasses. Thats the only thing you need.
You can airsoft in a tshirt. Shots will sting briefly, but it passes. In the 3-4 years I was playing, and we fired probably hundreds of thousands of BBS, I was aware of one tooth being knocked out, and you can choose to wear full face masks that will prevent that. Both the safety glasses and mesh masks are cheap.
Chronographs can be used to measure the FPS of a gun, and you can set field speed limits. I’m also aware of places that rent guns for game use.