I can say that Arsenal will win other matches, but in the case of Sevilla I am not sure, they are quite a strong opponent, despite the fact that they will play their last match before the Champions League against Real Madrid. I'm sure they will be able to give their best in both matches and do it successfully
Arsenal and Sevilla are competitive this season, they are favorites to qualify from the Champions league group B because they're fierce in performance and have the necessary qualities to explore in games. Perhaps Arsenal currently second with 3 points while Sevilla have 2 points, the team topping is Lens with 4 points rank, though the resulrs is shocking. This is UCL and there's alot of things that need to comprehended when it comes to UCL games, no room to underrated any team, results doesn't go according to plans, rather it moves to were it feels is suited.
It's entirely possible that Lance won't make it out of the group, but it's likely to be either a fluke or a mistake by their opponents. I'm leaning towards the second option and believe that Sevilla and Arsenal will get out of the group 100%. Lance were clearly not favourites against Arsenal, they only had 33% possession of the ball and were inferior to Arsenal in all aspects of the game