I don't think they should feature Midnight.
It would send the message that they can't support a movie on their own. Either it has to be like Shanghai Noon with Owen Wilson backing up Jackie Chan, or it has to be like Rush Hour with Chris Tucker backing up Jackie Chan. If it's not the whites having to help out the Asians, then it's the blacks.
They need to let Shang Chi stand on his own and have this an all-Asian cast. No sticking anything else in it, even something potentially Wakandan.
The other assassins should just be Asian as well.