The wonder cards (notice: there's an 's') ALL not stored on the Switch. We have an event page, you can view them all there.
They're not inject-able. This also isn't a question thread. I literally posted this above your post, and the guy above you acknowledged it. edit: Shifted this line of conversation to FAQ thread
There is however, this thing called "Wonder Card Records", which records some data from the wonder card.
That does contain some data, but as you mentioned, there is no deliveryman in the games, so even if you inject that, it won't allow you to receive an event.
It's merely for us to cross check and confirm details of an event.
Though, we presently have a way to obtain wonder cards from the system, and PKHeX can convert them to a file to a PB7 and inject them straight into your box.