When we already had a fit Sané Kun Sterling and Jesus we still tried to sign Sanchez last Summer. We had a look again this month but are now looking elsewhere.
Whether we have injuries or not we will sign a fifth forward at some point.
There is not another 17 year old getting into any other elite team in Europe that I know of so why would that be different at City? Neither Foden nor Diaz have shown they’re ready in terms of ability (a good U17 WC isn’t showing readiness for an elite European open age team), and neither of them look physically ready. Both have lost the ball by being outmuscled very easily in game time they’ve both had so far.
What you’ll notice about youth players moving on, they move on when they aren’t good enough. If they were good enough they’d get games.