The game's controls would ultimately be changed from the ones found in the previous entries. 2K would state that this was to "streamline" the game for newer players, however they were actually changed because 2K felt they needed a fundamental yet minor change to signal in the new development era.
Contributed by SOGESNAKE
The WWE 2K20 SmackDown! 20th Anniversary Collector’s Edition would normally come with a "Legend Autographed Plaque" of either Edge, Kurt Angle, or Rey Mysterio. However, many fans would receive a plaque without a autograph. While 2K had remained silent about the issue for days, Adam Copeland (Edge) would respond via Twitter about the issue telling fans they could mail their plaque's to his P.O. box, and he would sign each of them after returning from his movie shoot.
Contributed by SOGESNAKE
The two high school kids seen in the beginning of WWE 2K19's MyCareer mode can be seen in the background in the beginning of 2K20's MyCareer mode.
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Depending on the arena chosen in a Hell in a Cell match, the color of the cell will change. When playing in the Hell in a Cell arena or a RAW arena, the cell will be colored red. Playing the match in any other arena will result in the classic cell color.
Contributed by SOGESNAKE
Although a new system for blood appearing in matches was added to the game, it ultimately didn't work. Even when the game would state that a superstar had started bleeding, blood would not show up on the model.

A work-around was eventually found when viewing the moment a superstar starts bleeding through the Highlight Reel, blood would become visible in the match afterwards.
Contributed by SOGESNAKE
WWE 2K20 was so poorly received due to its quality that WWE 2K21 was cancelled in April 2020 and the series would not release a new title for almost 3 years.

The general state of the game can mostly be attested to long time developer Yuke's departure from the series in August 2019, 3 months before the game was eventually released. 2K would shift development over to their NBA developer Visual Concepts, but they would ultimately have many issues taking over another developer's project months before release.
Contributed by SOGESNAKE