Is it possible to make a mod for the game where you can keybind orders?

For example I usually get a light + grenade launcher and drop them with a box, however setting this order up usually take a while and if I press something wrong or forget a part of the order, like not selecting the proper delivery system, the order is more or less a waste of cash. However if I all needed to do was to press 1, and I'd get straight to the placement of the order, it would make the game much easier to play.

Does anyone know if this kind of addition to the game is possible?

Not directly, but you could (mostly) easily simulate the effect with some lua scripting.

Basically, make a lua controlled actor that moves along the ground like the point designator, and when you press 'fire' create a dropcrate above the scene at the position of the designator. Time delay optional. Then just have the 1 key spawn the actor.

You'd need a global lua controller, probably a brain, to do it, but it'd be pretty easy.

That or just carefully set up the preset beforehand. Or do you mean as the first purchase of each map? The presets system is still relatively vestigial, presets aren't carried on once you close the game (or is it each map? idk, point holds) but they're useful for getting lots of the same thing in one game.
However I suppose that point is redundant if you only have one favorite loadout, as they're carried on between purchases anyway...
Wow that whole post was redundant, smallified for those that don't want the clutter What paul proposed was closest to what you want I suppose, but you'll need some lua knowledge first.

Button macros?