I did try to pose a theory in one of my earlier posts.
Quite a few prolific attackers from Bundesliga went to Premier League and failed to come close to their Bundesliga tally. Mickhitaryan, Werner, Haller, Havertz, Sancho. PL is well known for being physical, fast paced, regularly high intensity. It takes freakish ability like Haaland, Aubameyang posses for them to adapt well in PL.
Choupo Moting is a reliable squad player for Bayern. Recently he even starts game regularly and being prolific. He was not the most stand out forward at Stoke few years back.
From the highlight, Weghorst is slow, but somehow Bundesliga defenders are mostly as slow, or even slower than him. He clearly in many cases had a lot of time. Weghorst is less instinctual, more about reactive with his poaching, shooting. Being more restricted with time and space, his scoring is worsen off maybe?
Also Weghorst looks like he was given penalty duty, so his stats improved.
https://www.transfermarkt.us/wout-weghorst/elfmetertore/spieler/228645
For his decent scoring record, he barely scored in European competitions. Not even a proper handful! Never scored in CL (Wolfsburg did play in CL for a season when he's there).
https://www.transfermarkt.us/wout-weghorst/alletore/spieler/228645
I don't like how he get started in more important games. I have no complaint for game like today or against Southampton (not his fault for us to not win the game. VAR took advantage of Casemiro mistake). There is nothing new about Weghorst performance. He has positive energy, but he severely lacks quality. Even his better performance in more optimal situation still lack end product. Unless he significantly improves (unlikely), there shouldn't be talk about making him permanent next season.
I recently realize Muani moved last summer for free. While we can't always get Muani type free transfer, even Welbeck level of yesteryears free transfer would be an improvement on Weghorst. Our scout seriously need to earn their wage. Hard to believe they can't find a better player.