Not exactly what you ask for, but some reviewers measure it like this: https://www.rtings.com/monitor/tests/inputs/input-lag https://www.rtings.com/monitor/test

Not exactly what you ask for, but some reviewers measure it like this: https://www.rtings.com/monitor/tests/inputs/input-lag https://www.rtings.com/monitor/tests/inputs/input-lag