For me it switches weapon sets with the F1-F5 keys though I have the original DVD release with the expansion not the digital. At least in that case 1-5 for combat arts and F1-F5 for weapons is the default binding.
Now I just have to unlearn my bad habits so I can use all the combos and CAs more effectively.
The game luckily very flexible so maybe you not have to forget everything and learn all new things. When you create the character you can set if you want faster cooldown that drain all combat arts, or slower but the differet aspects are on separate cooldown. It is fun messing around with builds. :)