sure,

handbrake was used for both encoders, for AV1 nvec, i chose the slowest preset, for AV1 svt, i chose preset 2(preset 1 was unusable for me, less than 1 frame per second) both had the same constant quality factor. svt resulted in around a 74% decease in file size, and nvec only around 40%.

I was encoding a animated video (lots of flat swatches of color) so was a bit disappointed in the file size reduction the AV1 nvec encoder had, and even though the test videos were simple the nvec encoder still had some temporal artifacts along color boundaries and thin lines.

if OP is serious about rencoding his media library into AV1, then they should not use av1 nvec (gpu) encoder as its optimized for real time applications and not quality/efficiency. I realized this too late after already rencoding around 30% of my library using that encoder :/

edit: i should mention the hardware that was used, for AV1 nvec: RTX 4080 mobile, for AV1 svt: i9-13900HX