I'm sure Arsenal will win in this match, Chelsea is a bad team and can't compete against top teams.
Chelsea previous matches: they beat Brighton which currently in bad performance too, Fulham and Burnley (two mediocre teams).
Arsenal previous matches: they beat Manchester City aka toughest team, unlucky lose against Lens (but Chelsea is worse than Lens).
So it's obvious Arsenal will win, the odds is high too, don't miss to bet Arsenal to win @2.15.
For now, what you said regarding Chelsea is correct, it is quite surprising to see that Chelsea is only able to achieve positive results when they meet clubs that are classified as mediocre. Of course, this is not in line with their shopping list last summer, which looked extravagant but did not meet expectations and provide the expected impact, for now I also doubt that Pochettino squad can finish in the UCL zone. And as you said Chelsea it is difficult to compete with other top clubs in the EPL. In the match Chelsea will only have an advantage because they are playing at home, Arsenal are very confident with their positive trend, but I think both will play a draw.
On the other hand, Arsenal impressive and unbeaten performance so far deserves appreciation, Arteta squad has been able to appear consistent and looks more promising than Chelsea this season. Hopefully Arteta will be able to bring the Gunners to the EPL trophy that fans have been waiting for for twenty years, and can compete in the UCL and win this trophy for the first time. Arsenal, who appear confident with their current performance, should be able to do this and emulate Chelsea success in previous seasons.
In my opinion, so far Pochettino is still having difficulty really getting out of the difficult zone to face how difficult it is to compete in the Premier League even though he is the coach of the big club Chelsea. The reason is that this season he is faced with an unbalanced player composition. Striker with an unclear role and doubtful abilities. Maybe he can only rely on Sterling because he is experienced enough. Palmer is a better choice than Mudryk. But the problem is, after the international break and facing Arsenal, a mature strategy and ideal player composition are needed. Pochettino still finds it difficult to show this to ward off Arteta aggression on the field. Because today what I saw from Arteta is that he is becoming more aggressive in implementing strategy. Successfully breaking Pep Guardiola when he didn't have the key to attack is an achievement that is considered extraordinary.