How to connect X to Restream
Navigate to your Restream Dashboard and click on the "Add/Edit destination" button.
Click "Add Channels", choose the X icon from the menu of destinations and click on "Connect X".
You would then need to authorize Restream to access your X account by clicking on "Authorize app".
You are now ready to stream to X!
Resolution: 1280 x 720 (recommended) and 1920 x 1080 (maximum)
FPS: 30 (recommended) and 60 (maximum)
Keyframe Interval: 3 seconds
Max Bitrate: 9,000 Kbps (recommended) and 12,000 Kbps (maximum)
Max Bitrate: 128 kbps (maximum)
Sampling Frequency: 44.1 (AAC)
You can find more information here.