The film and its principal credits
Sony's official record identifies Venom: Let There Be Carnage as a 2021 superhero film directed by Andy Serkis. Tom Hardy returns as Venom and Eddie Brock. Kelly Marcel wrote the screenplay from a story by Hardy and Marcel, and the cast includes Woody Harrelson, Michelle Williams and Naomie Harris.
The older Venom 2 shorthand refers to this sequel. A second trailer is another promotional release for the same film, rather than a second sequel or an additional chapter. Trailer numbering describes the marketing sequence, not the order of the story within a franchise.
Source [1]The film and the game crossover
Epic's September 2021 Fortnite announcement explicitly described its Eddie Brock outfit as inspired by Let There Be Carnage. That supplies a direct connection between the screen promotion and the game cosmetic. It does not turn the Fortnite outfit into another movie appearance or guarantee that the item remains on sale.
Sony's film page is the useful source for credits; Epic's announcement is the useful source for the crossover. Keeping those roles separate avoids attributing a game-shop feature to the filmmakers.
Source [2]