Would you swap Sanchez for.....?

Wouldn't swap Alexis for anyone in the league as far as attack is concerned. Hazard may just be the most over rated player around right now, the guy has no productivity to show to be even compared to Alexis.
Di Maria is a great player but again no.
Aguero great player but no...plus too injury prone.

But I would swap Welbeck for any half decent defender

Aguero all day long

Di Maria, no. Good against dross, struggles against top sides, not the man you want when you're struggling, unlike Sanchez.

Hazard, probably yes. Slightly better player plus 2 years younger.

Aguero, definitely. The striker with the best goals to minutes record in the history of the PL - nothing to add.

Aguero would be the dream signing

I would sell Sanchez and give £20M if it meant we got Aguero

Why Aguero though? The guy would be injured most of the time with us.

I wouldn't swap him for any of them, as he's an Arsenal player and I have an emotional attachment to him now (some homo).

Aguero is the one. However, with our medical team and his often average injury record he'd end up Diaby mark 2

I wouldn't swap him for any of those 3 players even though they are all arguably better than him. There's no guarantee they would fit in the way Alexis has with us. Look how Ozil has turned out.

Ozil came from being a luxury player being Ronaldo, Benzema and Di Maria with Modric and Khedira behind him, to playing with Giroud and Arteta. No comparison to players already settled in the league like Aguero and Hazard.

Aguero yes, but not Hazard or Di Maria