Arsenal's squad without Martin Ødegaard is not complete, and I don't think that Arsenal has great players on the bench who can replace him and perform as well as he does in midfield. His injury is a bad thing for Arsenal because it will surely affect their performance. Anyone who regularly watches Arsenal matches knows that Martin Ødegaard is one of their great players, doing an excellent job in the squad.
It is undeniable what Martin Ødegaard brings to the Arsenal team, he combines very well with Saka making that wing very effective, and his creativity is second to none in the Arsenal team. Arsenal will be missing his presence, but there are still enough options for Arteta to select for that game against Tottenham and the few other games he will miss. There is Jorginho, Ethan Ewaneri and Havertz who can drop back to midfield and give Trossard the chance in front while Sterling takes his place. I am sure Arteta should have a plan for that, there is enough time to plan for it, and lucky for Arsenal Odegaards Injury is not so severe.