RahiMew can mew. Since Rahi is technically RahiMew, Rahi can mew while acting like mewing, even though Rahi is mewing cutely like RahiMew does. Mewing is different from Rahi's mew, so mewing while doing a mew is confusing, but if you are mewing like Rahi acting like RahiMew, then probably you can mew while mewing, but not that effective. So, RahiMew can definitely mew as Rahi can mew. Though, if you mew while mewing, then what is the point of mewing if you have mewed like how Rahi mews like the real RahiMew? So, you can try not mewing while you mew. That is okay, since your mew can be most identical to Rahi's mew as RahiMew.