I don't think we'll have a more difficult match all season. City have an incredible squad, better than current CL holders Real Madrid imo. Having said that, we gave them a game in the CL final and they suffered to win it. This game is tougher though as it's in their home stadium.
Dimarco out so are Arnautovic and Buchanan. Correa not in the CL list.

Duo left out of Inter squad for Champions League game vs Man City
Inter's Federico Dimarco and Marko Arnautovic did not train with the rest of the team today and won't be available for selection for a Champions League game

Man City vs Inter: Probable line-ups
Inter (3-5-2): Sommer; Bisseck, Acerbi, Bastoni; Darmian, Barella, Calhanoglu, Zielinski; Taremi, Thuram.
Man City (4-2-3-1): Ederson; Walker, Akanji, Dias, Gvardiol; Rodri, Gündogan; Bernardo, De Bruyne, Grealish; Haaland.

Champions League: Man City vs Inter - probable line-ups and where to watch - Football Italia - September 18 latest
Reports in Italy suggest that Simone Inzaghi could drop his captain and last season’s top goalscorer Lautaro Martinez for Inter’s heavyweight Champions League

FI thinks we'll start with 10 players 😀 they forgot Augusto in that lineup.
Lautaro might be rested for the derby. He is yet to score this season..
The main reasons Inter lost to Atletico last season were missing chances and lapses in concentration in defence, those have to be avoided tonight. Our defence will be under a lot of pressure as it is, can't afford giving away cheap goals. I doubt we'll create a lot so we have to take our chance when it comes. Our first half wastfulness in Monza cost us.
City are the favourites to win and a loss tonight doesn't compromise Inter's European season as we still have 7 more games afterwards, but let's give it a go.
We won on our last visit to an English stadium, 0-1 at Anfield in 21-22. We also won away at Highbury in 03-04 and at Stamford Bridge in 09-10.
Forza Inter.