The Community Shield title is not actually a major trophy and I think here Manchester City will also take it easy to win this trophy. On the other hand, Manchester United will probably be more serious about winning it and at the same time it will be a good additional trophy after previously winning the FA Cup trophy.
I don't remember the last time Manchester City took the Community Shield so seriously and at that time Arsenal were always able to beat them in this match. However, I will not assume more and sometimes Pep Guardiola could be quite annoyed because last season they only managed to collect one EPL trophy and maybe this time they will try to win the Community Shield. Looking at the betting odds, Manchester City is far superior and does not consider Manchester United as a worthy challenger, but the over goal option here will be able to secure a safer bet than betting on one of them.
It's true Community Shield isn't a major trophy, but come on, they already take a long break and now this the first serious match before starting the league. It's not make sense if Manchester City can't perform since they're not tired anymore, they should able to give all out in this match. Although, the big upset that Manchester United won in FA Cup really make them can't be underestimated.
But, there are many of Manchester United's players injured, this time the luck will not be in their side.
But, hopefully with the number of Manchester United's main players injured it does not make Manchester City underestimate Manchester United. Because after all, if Manchester City underestimated Manchester United, it was still very possible for Manchester United to win in the FA Community Shield match later. Indeed, in comparison, of course Manchester City are still a better team but after all, in the FA Cup final match, Manchester City were also the favorite team to win the trophy, but in reality Manchester City can still lose too.
With this factor, then I personally think the factor of underestimating the opposing team can be very bad for the results for the Favorite team. Because even though Manchester United has a lot of injured main players, of course Manchester City must still be able to consider this match as a difficult match. Thus, Manchester City will play with a good effort of course to get the trophy before next season starts.