Usually they ask you to not promote the games or tv shows. See "the expanse" author IAMA on Reddit, they refused to discuss the tv show due to strikes (legends, since half the questions were about it)

I think some "influencers" can join SAG-AFTRA, and there was a provision regarding promoting striked work through online posts/podcasts/etc

Edit: Adding a link with details rather than my half-remembered stuff https://www.sagaftra.org/influencer-agreement-fact-sheet