>>45498235My mistake, it was in the June 2009 issue of coro coro when Lyra and Ethan's designs were first revealed, though they are only labeled protagonist-boy and protagonist-girl in this issue.
The boy's text roughly translates as "the boy with his signature gold streak (referring to his hat), he wears it on his left wrist (the pokegear). The girl's text roughly translates as "this new girl appears to be active, look how she hangs it from her bag" referring to the pokegear clipped to her bag.
I'm not sure if coro coro or Gamefreak writes up these releases, but it would have been reviewed and approved by both channels before being published. I remember when serebii, bulbapedia, and marrilland first reported she was a new character, a lot of fans were confused because the two looked so similar and it seemed like an odd decision on Gamefreak's end. The anime followed suit, introducing Lyra for a mini-arc instead of reintroducing Marina (who had already made a cameo appearance with an updated design and outfit in an earlier of the DP series).