In AQ, it is possible to open multiple projects at the same time and copy/paste items from one to the other.
With the quotes open, select the item you wish to transfer so that it is highlighted. If the item has accessories, just select the base item line.
For multiple items, either hold CTRL as you select the items or select the top item, hold SHIFT, and select the bottom item. To select all items in the quote, press CTRL + A.
There are 3 ways to then copy the items. The right click menu, the Copy button at the top or the hotkey CTRL + C.
The same 3 ways can then be used to paste the items into the other quote (the hotkey is CTRL+ V)