England thrashed Ukraine 4-0 in the quarter-finals on Saturday at the Stadio Olimpico in Rome to punch their ticket to the semi-finals.
Sancho, who will complete his sensational move to Manchester United after the Euros, finally made his first start for England at the Euros against Ukraine.
Jordan Henderson also came off the bench and replaced Declan Rice in the second half, with the Liverpool captain scoring a close-range header to complete England's win.
Gareth Southgate has been willing to drop his England stars as he rotates and shakes up his tactics at the Euros.
Speaking ahead of the Denmark clash, Wenger has predicted that Sancho will be dropped for the semi-finals.
However, the 71-year-old legendary Frenchman admitted that Henderson could be "important in the semi-final."
Wenger told beIN SPORTS: "Going forward he [Southgate] still looks for the perfect solution.
"I'm not sure that Sancho will play in the semi-finals, but he has 10 players he knows he will play.
"Personally, I like Henderson as well when he comes on because from deep midfield he plays forward, very good balls and I think he could be important in the semi-final.
"So, he has learned a lot about his players, he has learned himself a lot. That comes good now and I'm convinced they will be difficult to stop."
Sancho impressed during his performance against Ukraine as England fans were keen to see the 21-year-old winger start at Euro 2020.
Southgate has also used Bukayo Saka, Phil Foden and Jack Grealish in his England attack force alongside Harry Kane and Raheem Sterling.
Despite predicting that Sancho will be dropped for England's match, Wenger claimed the outgoing Borussia Dortmund star is a "mix between Grealish and a winger."
The legendary former Arsenal boss explained: "He wants to attack the flanks that the system Ukraine is playing.
"Many people ask why Jack Grealish doesn't play. I think Jadon Sancho is a mix between Grealish and a winger.
"He is a very creative player, similar to Grealish, but he is more of an incisive dribbler and that's why maybe he got the priority tonight."
England and Denmark will clash on 7th July at Wembley, with the winner to play either Italy or Spain in the final.
Featured Image Credit: PA/beIN SPORTS
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