I like their voices a lot, too. They both sound very familiar but I can't place them.
No you’re right, it’s definitely the same voice. We already knew that was Purah talking because of the “click snap”. I did look that up and apparently it was Kate Higgins. I think it’s safe to assume the same here in AoC.The unimpressed expressions of Impa, Zelda, and Link get me every time.
I was curious if we we're going to see these two and I'm glad for it, even if they don't end up being playable. Their designs seem fitting and they appear to be just as eccentric as ever, so I look forward to the comedic relief they'll inevitably provide.
I'm not sure about Robbie, but to me, Purah's voice sounds remarkably similar to the one taking the picture of the Champions in the BOTW DLC. I haven't looked up the voice actor, but if true, that would be a neat little connection to the main game. I'm sure they've done other voice acting work though, so maybe that's more what you're thinking of!