I don't think NU FC will meet Southampton who have just returned to the EPL, of course they will try hard not to fall back into the relegation realm, and I Southampton will surprise NUFC even though they will visit NUFC's headquarters, in this case it is not impossible because Southampton has a new style and of course new performance so it is difficult for NU FC to conquer them.
but on the other hand with the Man United match against Fulham at the opponent's home I think this will be an easy start for the red devils not because the other Man United currently has a new aura with big names their demands are very high this season so I think they will take advantage of this match by successfully getting three points early on.
I think City will have a little difficulty with what happened in the pre-season with Chelsea's defeat I think their new coach will evaluate in such a way that this match becomes interesting, and I think City can bring victory but it will be difficult for them, visiting Chelsea's headquarters is indeed not easy but I am still sure City will win even though it is a little difficult for them.
In the early season matches it is quite difficult to make predictions because we have not seen the real strength of the team and in my opinion what is seen in friendly matches cannot be used as a reference.
Man United may be slightly favored because they will play at home but I think Fulham also cannot be underestimated and as I said earlier that in the early season matches we cannot measure the strength of the teams so it is also possible for surprises to occur especially now that many of the Man United squad are injured.
Nothing is easy indeed but if you can see realistically that City's strength is better than Chelsea but this is a match between two top Premier League teams which makes the match will run with high tension because the prestige of both top teams of course wants to seize maximum results but it seems I have the same confidence as you that Man City will be able to overcome Chelsea's resistance in the first PL match this season.