I was sceptical when Conte said Kulu could be a wing back, but now that I think about it he'd be an excellent wingback.
He'd be like TAA but with physcality. That run Sess made for Kulu's cross, there's no reason he couldn't be on the end of a cross like that from Son or Perisic while playing as RWB. Simiarly, there's no reason he couldn't be delivering that cross as a WB either.
He works hard in defence and has the energy to go up and down the pitch, though his actual defensive quality is hard to judge unless we see him play WB.
I'd be curious to see how a front line of Son, Kane, Richarlison, with Kulu as RWB would work, as a more aggressive formation when we're chasing a result.
A lot of what Emerson does offensively is to just carry the ball up the pitch and give a short pass to Kulu, who then delivers the killer cross. Maybe he can do that job himself.