16:45:16.008: Windows Version: 10.0 Build 18363 (release: 1909; revision: 1316; 64-bit)
16:45:16.171: output 0: pos={0, 0}, size={2560, 1440}, attached=true, refresh=165, name=Q32G2WG3
16:45:16.171: output 1: pos={2560, 364}, size={1920, 1080}, attached=true, refresh=60, name=C32F391
16:45:16.171: output 2: pos={-1920, 381}, size={1920, 1080}, attached=true, refresh=60, name=C32F391
Windows has a long-standing bug when running multiple monitors at different refresh rates. It is fixed in Release 2004, but you are on 1909. Either update Windows, or set your 1440p monitor to 60fps.
16:59:22.503: YUV mode: 709/Full
Switch RGB range back to Partial. Unless you have a complete Full-range pipeline, this causes color issues, and is a very common new-user mistake.
17:06:58.970: [jim-nvenc: 'recording_h264'] settings:
17:06:58.970: rate_control: CBR
17:06:58.970: bitrate: 50000
17:06:58.970: cqp: 20
17:06:58.970: keyint: 120
17:06:58.970: preset: mq
17:06:58.970: profile: high
17:06:58.970: width: 2560
17:06:58.970: height: 1440
17:06:58.970: 2-pass: true
17:06:58.970: b-frames: 2
17:06:58.970: lookahead: true
17:06:58.970: psycho_aq: true
Do NOT record locally to CBR. Record to CQP/CRF, which is a quality-target based rendering method. CBR is only used for streaming, and is both incredibly wasteful, and prone to quality choke.
Use the Quality preset, not Max Quality. 2-pass is meant for dead-file conversion, not live recording.
Disable Lookahead and Psychovisual Tuning. These generally just cause problems.
17:06:59.060: [ffmpeg muxer: 'adv_file_output'] Writing file 'D:/Test OBS/2021-01-17 17-06-58.mp4'...
NEVER RECORD DIRECTLY TO MP4 FOR ANY REASON. It is NOT a recording-safe format, so if ANYTHING goes wrong during the recording or finalization, it will be irrecoverably corrupted, with NO way to restore it; just a pile of digital garbage that you have to delete and re-record. There's a reason it pops up a big orange warning message when you set the output to mp4.
As an added bonus, many video editors have major problems with the mp4 files OBS outputs when direct-recorded.
Record to MKV instead, and if you need MP4 files for your editor, use the 'Remux Recordings' option under the File menu.
You show no rendering or encoding lag in that test recording, so most likely the issue is being on Win10 1909 with differing refresh rate monitors. But the recording settings you're using are absolutely awful. 99.9999% of YouTube 'best settings' guides are complete crap from people who don't know what they're doing.
