Thank you for asking the question. For now, we don't have the function where you can import the word of the day into your flashcards or word bank.
For now, as you've described, only way to add the words introduced in the word of the day is to search them in the dictionary of the site, then add them manually.
I'll deliver your suggestion to our technical team, so we can find a way to develop the flashcard system as you'll be pleased.
If you have any questions, please let us know.