For those of us not familiar with TF2, you might want to be more specific as to what type of equipment you are referring to.
There are 9 classes in TF2, with these default loadouts (primary/secondary/melee):
Scout - scattergun (shotgun), pistol, baseball bat
Soldier - rocket launcher, shotgun, shovel
Pyro - flamethrower, shotgun, fire axe
Demoman - grenade launcher, sticky (grenade) launcher, whiskey bottle
Heavy Weapons Guy - minigun, shotgun, fists
Engineer - shotgun, pistol, wrench (for building immobile sentries, and stuff)
Medic - syringe gun, medigun ("weapon" with a healing beam), bonesaw
Sniper - sniper rifle, smg, kukri
Spy - revolver, sapper (destroys machinery), knife
The engineer and spy also have special "weapons" - engineer has a pip-boy-like apparatus for choosing buildings, and spy has a) an invisi-watch, and b) a disguise kit.
The weapons could all be easily made, if they don't exist already (minigun, shotgun, knife etc. exist), except perhaps for the engie's and spy's specials. Medigun could more-or-less be made with OXC Extended.
That being said, I don't know how well TF2 would work in X-COM, except for laughs.
