A CM who drifts in to wider positions can be VERY effective if his midfield partner(s) are capable of filling the space he leaves behind. It creates a significant tactical problem for the opposition by creating overloads.
I think it was Conte who at Juve had Pogba playing in a wider midfield role with players like Marchisio & Vidal filling the spaces and doing the leg work. You then had Pogba thriving in a way we've never seen since.
This is all speculation though, it may be we see Kulusevski as purely a wide player, but I'd be interested to see if we try and use him to fix our issue of lacking creativity in midfield.