Streamlabs can use your old phone as a relay link.

Source Summary

Network Boost is a new feature that aims to provide reliable connectivity for IRL streamers. It requires a Streamlabs Ultra subscription (which starts from $27 per month) and works by pooling cellular and local Wi-Fi connections together on both the iPhone you’re broadcasting on, and a secondary iPhone or Android device running the Streamlabs Controller app. [Link: Streamlabs Launches Network Boost: Flawless IRL Streaming, Zero Expensive Hardware | https://www.businesswire.com/news/home/20260804055102/en/Streamlabs-Launches-Network-Boost-Flawless-IRL-Streaming-Zero-Expensive-Hardware | Business Wire]