oh you’re not bothering me at all, mate : D I don’t know if any of these are among those you’ve read but here are the ones i’ve read and loved!
Not Everybody Has Got a Body Like You by queenklu
rated: teen and up audiences words: 4k summary: "Can you please explain to me why I have just turned Morgana into a toad?!"
Woke Up New by Zee
rated: explicit words: 21k summary: Merlin and Arthur switch bodies; complications ensue.
I would also recommend taking a look here, these two above is also listed there but it also have few others :)
Next Time, I Will Remember This And I Will Say “No” by paperclipbitch
rated: PG-13 words: 8k summary: “Arthur wants you to pretend to be him so that he doesn’t have to get married to Princess Helena?”
I would also highly recommend taking a look here, the one above is just one of my favorite but on that link you can find lots of amazing stuff. its like my number one place to look for fanfics. Bless fy-merlinxarthur
(this one isn’t a bodyswap or roles reversed but it’s still too wonderful to keep out)
Change in Crowns by derekstilinski
rated: mature words: 11k summary: Arthur has traveled to sign a treaty of friendship with other kingdoms, when he realizes they’ve intended to set him up to marry as well. He doesn’t want to marry for the sake of marrying, so he pulls a clumsy, crowned Merlin in with false talk that they married quietly.
Arthur’s true in saying he wants to marry for love, because he chooses Merlin for more than one reason.