Anachris is a cold water plant and tends to melt after coming home from the store, so if you decide to go with that keep it in a seperate tank and gradually increase the temps over a period of a week to the same temp as the main tank before you put it in.
Swords get a little too big for a 3 gallon, they're okay while small but grow quickly and tend to overgrow a 3g within a week or two.
The rest should all work, I'd switch out the duckweed for red root floater/frogbit instead, duckweed just gets everywhere, but really it's just personal preference.
The rest should all go great as long as the temps stay relatively stable and you provide some method of fertilization (snails make good plant keepers, they don't eat the plants and their feces are good fertilizers). You MAY need to use root tabs if the plants grow too quickly in the light, but you should be able to pull it off with what you have.
Do you have a filter or any method of water circulation?