Change weapons in Aquanox with 1/2 or left / right D-Pads, and duplicates are purchased at the docks with change.
Switching weapons in Aquanox: Deep Descent is pretty straightforward: just press 1 or Left on the D-Pad to scroll your left weapon, or 2 / Right D-Pad to use the right weapon. There's no radial menu to choose exactly what you want, and you also can't unequip whatever weapons you own, so be prepared to spam the buttons until you get the precise weapon that you own. you are looking for. If you pass, well, start pushing that button again.
As for duplicate weapons in Aquanox, they require a bit of finesse to purchase. On any dock, you will notice that the first tab allows you to upgrade your submarine. The bomb icon in this menu will take you to your weapons, and it is from here that you can purchase a duplicate weapon. However, there is a little trick to this: you will first need to equip the weapon you want to buy a duplicate of in one slot, look for the duplicate in the other slot. Yeah, I tried to see if there was another way, but it's so complicated.
Once you find the duplicate weapon, you will need to purchase it with cash. Most duplicate weapons in Aquanox work for 7 credits or more, so you'll need to complete bounties and sell gear if you want to treat yourself to one. Due to the high price, you'll want to prioritize one or two duplicates, otherwise you'll have a hard time keeping your submarine upgrades up to date. It's tempting to try and buy them all, but find what works for you, grab the upgraded version, then buy the duplicate. Otherwise, you'll find yourself constantly broke, and that will only make your time with Aquanox: Deep Descent even more boring.
