transcode into different resolution?

I downloaded a 8k by 8k (3D ToU) video from youtube and transcoded to 60fps using SVP.
Now I  want to play it in my quest 2 (which limit at 5760 by 5760),  I try to use the transcoder but cannot find a way to do so.
I added scale=720x406 in ovcopts and it doesn't work (no change in resolution),  any way to change the resolution?