When testing the new passkey functionality on http://en.wikipedia.beta.wmflabs.org/wiki/Special:AccountSecurity:
Before I enable 2FA, the section to add a passkey appears below the 2FA section:
{F71578054}
After I enable 2FA, the passkey section moves up and appears in a different place on the page:
{F71578059}
I suspect this is an intentional design choice, because users can't enable passkeys until after they have added a 2FA method. However, this behavior and UI inconsistency is unexpected to me as a user; I would expect to find these page elements in the same place on the page. When I went back to Special:AccountSecurity after adding a 2FA method, I was surprised that the Passkey section was in a dfiferent place.
Suggestion: put the passkey section between the password and 2FA sections permanently. The UI text explaining that you must enable 2FA before you can add a passkey is sufficiently clear.