Gaming I'd like to have some advice on account switching at the 3DS.

[Jordy19]

Without being aware of what I did I accidentally used another account on my Switch then I use on my 3DS meaning I have two accounts now.
Can I just erease the account from the 3DS and keep the game saves that are from the psychical game cardridges, none are bought online, I do own all the games and their cases.
Would the Pokemon Crystal and Pokemon Gold 3DS codes used on the account of the 3DS also work on my primary account that is connected to my Switch?

Thank you in advance.

I hoop that this is the right section for this question, if not. Let me know!