The bank if telling me i need to free a slot for wonder card, so i assume i can only hold 1 at a time.. past generations games could hold up to 3.
If your party is full, yes, but I don't remember.
All you need is a free wondercard slot. You also have more then one one WC slot. Go from there. --- 3DS FC: 4656-7454-0042 FS: Flying Type, Pidgey, Tranquill, and Rufflet I don't give people serious answers unless needed.