When Marvel Rivals released, it was discovered that several terms that were considered controversial in China (the home country of developer NetEase) had been banned from the game. The terms in question include "free Taiwan", "free Hong Kong", "free Tibet", "Taiwan is a country", "Taiwan No 1", "1989" (the year the Tiananmen Square massacre occurred), and "Winnie-the-Pooh" (who many have compared to Chinese president Xi Jinping via internet memes, resulting in the character being censored in China as a whole). Additionally, in a clip from a livestream by YouTuber Asmongold, it was discovered that while "free Taiwan" was banned, the terms "Taiwan sucks" and "Taiwan is bad" were not, furthering the censorship accusations. It's worth noting however that the censorship did not exclusively apply to terms related to China, as terms such as "ISIS" and "Hitler" were also discovered to be banned in the game, likely due to them both being more universally controversial.

According to a report from Bloomberg, NetEase CEO William Ding nearly cancelled Marvel Rivals before its release, partly because of the fact that the game was based on Marvel Comics IPs. Ding reportedly did not want to pay Disney for the rights to use Marvel characters and attempted to convince the game's designers to create original characters instead in order to save on development costs. While a spokesperson for NetEase would deny these claims, other NetEase employees claimed in the same article that Ding was indecisive and would frequently change his mind on major decisions like these.

A unique interaction between Spider-Man and The Thing has the pair make numerous references to classic Marvel titles, specifically "Marvel Team-Up" (a crossover series that saw Spider-Man teaming up with other Marvel characters), "Marvel Two-in-One" (a series with a similar premise to "Marvel Team-Up" except with the Thing as the primary character), and their respective comic series "Fantastic Four" and "The Amazing Spider-Man".