Ramazani, 16, has arrived from Charlton Athletic while Traore, also 16, who was being chased by Juventus, will join from Sarcelles after spending time in Paris Saint-Germain’s youth system.
United have already signed Northern Ireland Under-17 captain Ethan Galbraith this summer.
Ramazani, a striker, has signed a four-year deal at Old Trafford while Traore, who has captained France U17s, is set to agree a three-year contract.
It is the second summer of new arrivals following Nicky Butt’s appointment as head of the academy in February 2016.
Last summer, Dutch winger Tahith Chong, from Feyenoord and forward Joshua Bohui from Brentford were among a host of new signings.