https://www.researchgate.net/publication/340351958_MSU_Video_Codec_Comparison_2019_part_IV_High-Quality_Encoding_aom_rav1e_SVT-AV1_SVT-HEVC_SVT-VP9_x264_x265_EN

https://www.researchgate.net/publication/340351958_MSU_Video_Codec_Comparison_2019_part_IV_High-Quality_Encoding_aom_rav1e_SVT-AV1_SVT-HEVC_SVT-VP9_x264_x265_ENTERPRISE_VERSION https://www.researchgate.net/publication/340351958_MSU_Video... according to that (5. ENCODING SPEED section) SVT-AV1 is a bit faster, but since they are both VERY slow it doesn't really matter. That was released in March so recent updates might have changed things.