Seriously? No one here actually went and checked the rules?
Let me quote:
Duel mode specific rules
- All types of duels are allowed (ranged, mounted, shield, heavy armor...) if both duelists agree
- No following or face-hugging the other duelist before the duel countdown has ran out - either hold your starting position or back-pedal if you want some distance between you and your opponent
- No running away or going into unreachable places
So basically picking shit up is not allowed, but you can use the stuff on your back/sides if the enemy can see them/know that they are there.
If I wanna duel with more than one weapon, I first hold one weapon up, then switch to the other and
then press F. That makes it more clear that I use multiple weapons. Also, feel free to ban poll people who facehugs before the duel starts. It's in the rules.