Ten Hag manages a different team, the target will be also different. Also, the level competition in Bundesliga isn't the same as EPL. So, I think Ten Hag is possible to succeed with Leverkusen although it requires a better squad. The first thing that Ten Hag needs to do is to rebuild the squad. If he can sign some good players, we can expect that he can do better job in Leverkusen. TBH, I really hope Ten Hag won't repeat the same mistake that he ever did in Man United.
Manchester United and Leverkusen's squads are not the same. Manchester united's squad had a lot of star players. Ten Hag had no previous experience in managing such a squad. This was one of the reasons for Ten Hag's failure. However, on Ten hag's advice, Manchester United bought Hojlund and ANtony at a huge cost. Manchester United faced a huge loss. Ten Hag is definitely to blame for this.
Leverkusen's squad is not very strong . But the players are hardworking. They have the ability to perform well. Besides, I don't think leverkusen will fight for the title next season. The pressure on Ten Hag is low. If they can stay in the top 4 of the table, the Leverkusen management will probably be happy.