Indoor I could see proper shoes or those hiker/cross trainer things but outdoors I wouldn't trust anything without ankle support.
Take the advice from a boarder and former skier. Ankle injuries suck (especially for skiers). My mom twisted/broke her ankle once and was out for the remainder of the season AND had to do this physio stuff, not cool.
PS: That mask is likely fine. In fact probably good to have since if you're playing at a paintball field the insurance will usually stipulate ASTM approved goggles (paintball certification) and even though you may have Oakleys or ESS goggles that can survive a blast from a .50 cal it's still not ASTM approved and as such if a claim goes through the insurance company will deny it on the technicality (they don't want to pay out money so will try to find anything and everything you've done wrong).
ಠ_ಠLess QQ more Pew Pew
READY TO >> RACE