You can't miss Veron from any list like that. He was the daddy for many years.It depends how you define flop. He hasn't been great, but the entire team is a flop. Pogba, to many, is still one of the most talented in an awful team. It is not like he is out of his depth amongst those players. So, if you are purely going on transfer fee and whether a player was part of a successful side, then your definition could be correct (also need to consider the inflation of transfer fees through the years). But, not necessarily if you are just going on how bad the player was within the team they became part off.
Forlan, Kleberson, Djembe Djembe and Sanchez were arguably bigger flops at Utd. Bentley and Rebrov at Spurs. Kezman, Shevchenko and Mutu at Chelsea. Boumsong at Newcastle. Diao, Aquilani and Carroll at Liverpool. Brolin at Leeds. Jeffers at Arsenal.
Personally, I would rather have Pogba in my side than many of those players, even if it meant he was still more expensive after inflation was accounted for. I'm not saying Pogba is amazing, but there have been some stinkers in the 30 years of the Premier League, I bet there are more than I forgot about.