There are a LOT of different sword plants, but unless it's potted with a tag that gives the actual species or cultivar name, amazon sword is often the catch all name given to the ones without ID.
Some can stay relatively small, some can grow three feet tall, some sprout plantlets like mad, some make new plants rather slowly. Some are variegated with red or white, or even vari-coloured green spots on one leaf. If you look up a site like 'the planted tank', you'll find IDs on many of the common sword plants and see the variety there is in this group.