Which Xbox do you have?
Series X
On series-X we can do screen capture in 4k (series-S 1440p) It’s higher quality and faster than the in game export feature.
Go to xbox settings - preferences - capture & share.
Here you can enable screen capture and adjust quality.
You also must map one of the share button presses to start/stop recording.
Back In the game you can now start the screen recording, hide the editor hud and play your edit, when your edit is finished, stop the screen recording. (You can also use this feature now to just capture regular gameplay as well)
A few seconds later it will be available in the captures app.
You can export this to a hard drive to get the 4k video for editing or you can just send it to the xbox mobile app but this will downscale to 1080p.
Video Tutorial attached.
