Talking about players outside the English Premier League who can perform well but fail in this league, it cannot be denied, apart from the names you have mentioned. Currently, some players have not been able to perform brilliantly even though they were bought at a fairly high price and that is because of their appearance so brilliant at their previous club that their current club believed they could perform well and contribute as expected but apparently failed, there is Mudryk at Chelsea and also Darwin Nunez at Liverpool.
Mudryk was bought by Chelsea at a high price from Shakhtar Donetsk, apart from the fact that this club was also going through bad times, which made Mudryk look even worse, but also when playing Mudryk doesn't appear worth the price to bring him to this club.
Nunez may still be better but he was still not Klopp's first choice in the previous two seasons. Liverpool were just luckier than Chelsea because Nunez had progressed in his second season.
It seems like the clubs in the English league value the players they are targeting outside this league too highly, that's why when they don't perform well it will make the player look bad because the price will described the expectations for the player.
This is why I was always favouring getting inside. Doesn't mean that you should get all English players, or not even British. I think it is quite clear that we are talking about a situation that is a little different, like just get players who played at premier league. Like for example, I am sure Kane was untouchable for a long time, but if I could, I would have bought him when he was younger if I was City, they had the money, and could have done so well, well they did but still, you get what I mean.
If any team with money wants to do better, like Chelsea for example, they could just get players in premier league that has done well, if they do that then they are going to have less shock and the result should be fine.