Hi Miguel- Julianne from Mixpanel Support here.
Currently, the Session Replay feature is not supported for the React Native SDK in Mixpanel. The primary focus for the Mixpanel team is to get native iOS and Android up and running. After both native platforms are fully supported, they plan to begin work on cross-platform support. Unfortunately, there are no specific timelines available for when this feature will be available for React Native.
Apologies for not having better news there!
Enabling Session Replays with React Native SDK | Mixpanel Community